[libunwind] Permit additional compiler and linker flags to be passed to tests.

Summary:
This is done via new LIBUNWIND_TEST_COMPILER_FLAGS and
LIBUNWIND_TEST_LINKER_FLAGS variables.

Reviewed By: sdardis

Differential Revision: https://reviews.llvm.org/D43585


git-svn-id: https://llvm.org/svn/llvm-project/libunwind/trunk@326223 91177308-0d34-0410-b5e6-96231b3b80d8
2 files changed