libclang_rt.profile*.a search path should use osNameUnversioned

[michael-yuji]

On platforms where the triple includes the os version, in this case x86_64-unknown-freebsd14.2,
the swift-driver is trying to link against various clang rt libraries in clang/lib/freebsd14.2, but the actual
clang convention is to have the libraries installed in clang/lib/freebsd instead, see clang/lib/Driver/ToolChain.cpp#L686.

Although the right solution is probably to implement getOSLibName in swift-driver; we can just use
osNameUnversioned for now as the only special case where getOSLibName != osNameUnversioned
is for Solaris, which is not yet supported.

[michael-yuji]

@swift-ci please test