hwasan: lay groundwork for importing subset of sanitizer_common interceptors [NFC]

This patch does the bare minimum to import sanitizer_common_interceptors, but
without actually enabling any interceptors or meaningfully defining the
COMMON_INTERCEPT macros.

This will allow selectively enabling sanitizer_common interceptors (if the
appropriate macros are defined), as suggested by Vitaly in D149701.

Differential Revision: https://reviews.llvm.org/D150708