[compiler-rt][AArch64] Readd SME ABI routines files to the build (#142953)
Commit 75c3ff8c0b29f374d31ba99e51852f7f6851a6c8 inadvertently removed
some files from the build related to the SME ABI routines.
This patch fixes the issue by reintroducing the files to the build in
CMake.