This patch removes some nondeterminism from direct object file output

for TLS dynamic models on 64-bit PowerPC ELF.  The default sort routine
for relocations only sorts on the r_offset field; but with TLS, there
can be two relocations with the same r_offset.  For PowerPC, this patch
sorts secondarily on descending r_type, which matches the behavior
expected by the linker.

llvm-svn: 170237