[compiler-rt][tests] Define TARGET_FLAGS

D36116 refactored the logic of tests and removed the definition of TARGET_FLAGS, but left one use of it. Restore its definition for that one use, so that an x86_64 test is compiled with -m64.

Reviewed By: vitalybuka

Differential Revision: https://reviews.llvm.org/D93634

GitOrigin-RevId: b01b964d3776956ef415a10c57cf612add55bba9
1 file changed