Allow cc_prebuilt version suffix to include `svn`

This commit allows cc_prebuilt version suffix to include `svn`, e.g.
`libclang.so.8svn`.  The rationale behind this commit is that latest
LLVM/Clang prebuilt binaries use `.8svn` as the version suffix.

Bug: 111579848
Test: header-abi-dumper builds with the latest binaries
Change-Id: I91594c5d8bc57605e2e0facb0a867dc4a4a17fe6