Add support for lorax-composer on other arches

[bcl]

This is a port of PR #603, including a few extra patches to support easier cherry-picking and tests.

--- Merge policy ---

• Travis CI PASS
• *-aws-runtest PASS
• *-azure-runtest PASS
• *-images-runtest PASS
• *-openstack-runtest PASS
• *-vmware-runtest PASS
• For rhel8-* and rhel7-* branches commit log references an approved
  bug in Bugzilla. Do not merge if the bug doesn't have the 3 ACKs set to +!

--- Jenkins commands ---

• ok to test to accept this pull request for testing
• test this please for a one time test run
• retest this please to start a new build

[atodorov]

I have uninstalled xorriso from the test system. I have genisoimage which provides mkisofs:

2019-02-21 07:54:22,984:   runcmd mkisofs -v -U -J -R -T -o /var/tmp/lmc-work-0hadlbu7/images/boot.iso -part -hfs -r -l -sysid PPC -A Red Hat Enterprise Linux 8.0 -V Red_Hat_Enterprise_Linux_8_0_ppc -volset 8.0 -volset-size 1 -volset-seqno 1 -hfs-volid 8.0 -chrp-boot -map /var/tmp/lorax.imgutils.av55jptp/tmp/config_files/ppc/mapping -no-desktop -allow-multidot -graft-points .discinfo=/var/tmp/lmc-work-0hadlbu7/.discinfo ppc=/var/tmp/lmc-work-0hadlbu7/ppc boot/grub=/var/tmp/lmc-work-0hadlbu7/boot/grub LiveOS=/var/tmp/lmc-work-0hadlbu7/LiveOS
2019-02-21 07:54:22,985:   subprocess.CalledProcessError: Command '['mkisofs', '-v', '-U', '-J', '-R', '-T', '-o', '/var/tmp/lmc-work-0hadlbu7/images/boot.iso', '-part', '-hfs', '-r', '-l', '-sysid', 'PPC', '-A', 'Red Hat Enterprise Linux 8.0', '-V', 'Red_Hat_Enterprise_Linux_8_0_ppc', '-volset', '8.0', '-volset-size', '1', '-volset-seqno', '1', '-hfs-volid', '8.0', '-chrp-boot', '-map', '/var/tmp/lorax.imgutils.av55jptp/tmp/config_files/ppc/mapping', '-no-desktop', '-allow-multidot', '-graft-points', '.discinfo=/var/tmp/lmc-work-0hadlbu7/.discinfo', 'ppc=/var/tmp/lmc-work-0hadlbu7/ppc', 'boot/grub=/var/tmp/lmc-work-0hadlbu7/boot/grub', 'LiveOS=/var/tmp/lmc-work-0hadlbu7/LiveOS']' returned non-zero exit status 2.
2019-02-21 07:54:23,488: traceback: Traceback (most recent call last):
  File "/root/lorax/src/pylorax/api/queue.py", line 143, in monitor
    make_compose(cfg, os.path.realpath(dst))
  File "/root/lorax/src/pylorax/api/queue.py", line 248, in make_compose
    run_creator(install_cfg, cancel_func=cancel_build)
  File "/root/lorax/src/pylorax/creator.py", line 701, in run_creator
    result_dir = make_livecd(opts, mount_dir, work_dir)
  File "/root/lorax/src/pylorax/creator.py", line 369, in make_livecd
    tb.build()
  File "/root/lorax/src/pylorax/treebuilder.py", line 312, in build
    self._runner.run(templatefile, kernels=self.kernels)
  File "/root/lorax/src/pylorax/ltmpl.py", line 141, in run
    self._run(commands)
  File "/root/lorax/src/pylorax/ltmpl.py", line 160, in _run
    f(*args)
  File "/root/lorax/src/pylorax/ltmpl.py", line 520, in runcmd
    stdout = runcmd_output(cmd)
  File "/root/lorax/src/pylorax/executils.py", line 347, in runcmd_output
    return execWithCapture(cmd[0], cmd[1:], **kwargs)
  File "/root/lorax/src/pylorax/executils.py", line 249, in execWithCapture
    reset_handlers=reset_handlers, reset_lang=reset_lang)[1]
  File "/root/lorax/src/pylorax/executils.py", line 201, in _run_program
    raise subprocess.CalledProcessError(proc.returncode, argv, output)
subprocess.CalledProcessError: Command '['mkisofs', '-v', '-U', '-J', '-R', '-T', '-o', '/var/tmp/lmc-work-0hadlbu7/images/boot.iso', '-part', '-hfs', '-r', '-l', '-sysid', 'PPC', '-A', 'Red Hat Enterprise Linux 8.0', '-V', 'Red_Hat_Enterprise_Linux_8_0_ppc', '-volset', '8.0', '-volset-size', '1', '-volset-seqno', '1', '-hfs-volid', '8.0', '-chrp-boot', '-map', '/var/tmp/lorax.imgutils.av55jptp/tmp/config_files/ppc/mapping', '-no-desktop', '-allow-multidot', '-graft-points', '.discinfo=/var/tmp/lmc-work-0hadlbu7/.discinfo', 'ppc=/var/tmp/lmc-work-0hadlbu7/ppc', 'boot/grub=/var/tmp/lmc-work-0hadlbu7/boot/grub', 'LiveOS=/var/tmp/lmc-work-0hadlbu7/LiveOS']' returned non-zero exit status 2.

[bcl]

There's some missing output there, probably captured in program.log I can't tell why it failed from just the error code. Also, I copied that over from the rhel8 template, so it really should work...

[atodorov]

with the latest changes I was able to build live-iso on ppc and boot the results with kvm.

[coveralls]

Pull Request Test Coverage Report for Build 1375

• 92 of 127 (72.44%) changed or added relevant lines in 3 files are covered.
• 1 unchanged line in 1 file lost coverage.
• Overall coverage increased (+4.7%) to 49.219%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
src/pylorax/creator.py	24	25	96.0%
src/pylorax/ltmpl.py	50	84	59.52%

Files with Coverage Reduction	New Missed Lines	%
src/pylorax/ltmpl.py	1	22.83%

Totals
Change from base Build 1374:	4.7%
Covered Lines:	2476
Relevant Lines:	4762

---

💛 - Coveralls