objtool: Fix memory leak in elf_create_rela_section()

Let's free the allocated char array 'relaname' before returning,
in order to avoid leaking memory.

Signed-off-by: Martin Kepplinger <martink@posteo.de>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: mingo.kernel.org@gmail.com
Link: http://lkml.kernel.org/r/20170914060138.26472-1-martink@posteo.de


Signed-off-by: Ingo Molnar <mingo@kernel.org>