MIPS: Fix memory leak in error path of HI16/LO16 relocation handling.

Commit 6f5d2e970452b5c86906adcb8e7ad246f535ba39 (lmo) /
477c4b07

 (kernel.org) [[MIPS: VPE: Free
relocation chain on error.] fixed the same issue in the vpe loader in 2009
but back then the same bug in module.c went unfixed.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Reported-by: Akhilesh Kumar <akhilesh.lxr@gmail.com>