[OpenMP] Add lock function definitions to fix Bug 40042

This change fixes the sanity issue reported in Bug 40042.
Lock function definitions for the three lock kinds were added
to disambiguate calls to the lock functions done directly and indirectly.

Bugzilla: https://bugs.llvm.org/show_bug.cgi?id=40042
Patch by Hansang Bae

Differential Revision: https://reviews.llvm.org/D56103

llvm-svn: 351224