FDB compiles on Apple Sillicon

[mpilman]

This is my third try...

This makes FDB compile on Apple Silicon with minimal code-changes. I did minimal testing so expect stuff to be still broken. Changes necessary:

1. Weird static initialization problem with knobs (fdbserver did immediately segfault)
2. Generate asm files
3. Use __bultin_prefetch instead of _mm_prefetch
4. Fix clock to work on Mac arm in flow/Platform.h

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[foundationdb-ci]

AWS CodeBuild CI Report for Linux CentOS 7

• CodeBuild project: foundationdb-pr
• Commit ID: 5af465a
• Result: FAILED
• Error: Error while executing command: if [[ $(git diff --shortstat 2> /dev/null | tail -n1) == "" ]]; then echo "CODE FORMAT CLEAN"; else echo "CODE FORMAT NOT CLEAN"; echo; echo "THE FOLLOWING FILES NEED TO BE FORMATTED"; echo; git ls-files -m; echo; exit 1; fi. Reason: exit status 1
• Build Logs (available for 30 days)

[foundationdb-ci]

AWS CodeBuild CI Report for macOS Catalina 10.15

• CodeBuild project: foundationdb-pr-macos
• Commit ID: 5af465a
• Result: FAILED
• Error: Error while executing command: ssh -o StrictHostKeyChecking=no -o UserKnownHostsFile=/dev/null -i ${HOME}/.ssh_key ec2-user@${MAC_EC2_HOST} /usr/local/bin/bash --login -c ./build_pr_macos.sh. Reason: exit status 1
• Build Logs (available for 30 days)

[foundationdb-ci]

AWS CodeBuild CI Report for Linux CentOS 7

• CodeBuild project: foundationdb-pr
• Commit ID: 28dde27
• Result: SUCCEEDED
• Error: N/A
• Build Logs (available for 30 days)

[sfc-gh-mpilman]

instead of __builtin_prefetch we should still use _mm_prefetch and include sse2neon.h -- I made this change