HPCC-16688 Add CBlas library to lib2 for APPLE

[xwang2713]

Also work-around Homebrew library symbolic link and multiple library copies:

1. cmake configuration finds openblas library under /usr/local/opt/openblas/lib with generic name which is symbolic link
2. libeclblas.dylib links real openblas library under /usr/local/opt/openblas/lib/
3. cmake get_filename_component finds real openblas library under /usr/local/Cellar/openblas/

Signed-off-by: Xiaoming Wang xiaoming.wang@lexisnexi.com
@Michael-Gardner please help to review

[hpcc-jirabot]

https://track.hpccsystems.com/browse/HPCC-16688
Jira updated

[HPCCSmoketest]

Automated Smoketest
Sha: 33f69a5
Build: success
ECL Watch: Rebuilding Site

errors	warnings	build time
0	65	90.65 seconds

Install hpccsystems-platform-community_6.2.0-rc5.el7.x86_64.rpm
HPCC Start: OK

Unittest result:

total	passed	failed	timeout
88	88	0	0

HPCC Stop: OK
HPCC Uninstall: OK

[Michael-Gardner]

@xwang2713 looks good