binfmt_elf: quiet GCC-4.6 'set but not used' warning in load_elf_binary()

With GCC-4.6 we get warnings about things being 'set but not used'.

In load_elf_binary() this can happen with reloc_func_desc if ELF_PLAT_INIT
is defined, but doesn't use the reloc_func_desc argument.

Quiet the warning/error by marking reloc_func_desc as __maybe_unused.

Signed-off-by: David Daney <ddaney@caviumnetworks.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

fs/binfmt_elf.c

@@ -570,7 +570,7 @@ static int load_elf_binary(struct linux_binprm *bprm, struct pt_regs *regs)
 	unsigned long elf_entry;
 	unsigned long interp_load_addr = 0;
 	unsigned long start_code, end_code, start_data, end_data;
-	unsigned long reloc_func_desc = 0;
+	unsigned long reloc_func_desc __maybe_unused = 0;
 	int executable_stack = EXSTACK_DEFAULT;
 	unsigned long def_flags = 0;
 	struct {