[libc-trusty] stop exporting non-standard macros from libc headers

lk/compiler.h was being used for conditional extern "C" macros, but the
preprocessor defines it added could conflict with other definitions. To
improve portability, we should not have non-standard macros and symbols
exported from standard header files.

Bug: 110158907
Change-Id: I5b7f5bb79bbca29f42b821a71ad372a00b493c92
3 files changed