libgcc_{eh,s}: restore __*_frame_info symbols post llvm18

The upstream llvm commit 5eb44df1b64d made the addition of these GCC
compatability symbols dependent on build configuration rather than
hardcoded for amd64, i386, and powerpc. Reenable them.

Reviewed by: dim
Differential Revision: https://reviews.freebsd.org/D44877