[clang] hexagon: fix link order for libc/builtins (#117057)
When linking programs with `eld`, we get a link error like below:
Error:
/inst/clang+llvm-19.1.0-cross-hexagon-unknown-linux-musl/x86_64-linux-gnu/bin/../target/hexagon-unknown-linux-musl//usr/lib/libc.a(scalbn.lo)(.text.scalbn+0x3c):
undefined reference to `__hexagon_muldf3'
libc has references to the clang_rt builtins library, so the order of
the libraries should be reversed.
(cherry picked from commit 9cc2502c048b1403ba8ba5cc5a655d867c329d12)