x86/tools: Fix gcc-7 warning in relocs.c

gcc-7 warns:

In file included from arch/x86/tools/relocs_64.c:17:0:
arch/x86/tools/relocs.c: In function ‘process_64’:
arch/x86/tools/relocs.c:953:2: warning: argument 1 null where non-null expected [-Wnonnull]
  qsort(r->offset, r->count, sizeof(r->offset[0]), cmp_relocs);
  ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
In file included from arch/x86/tools/relocs.h:6:0,
                 from arch/x86/tools/relocs_64.c:1:
/usr/include/stdlib.h:741:13: note: in a call to function ‘qsort’ declared here         
 extern void qsort 

This happens because relocs16 is not used for ELF_BITS == 64, 
so there is no point in trying to sort it.

Make the sort_relocs(&relocs16) call 32bit only.
Signed-off-by: Markus Trippelsdorf <markus@trippelsdorf.de>
Link: http://lkml.kernel.org/r/20161215124513.GA289@x4Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

arch/x86/tools/relocs.c

@@ -992,11 +992,12 @@ static void emit_relocs(int as_text, int use_real_mode)
 		die("Segment relocations found but --realmode not specified\n");
 
 	/* Order the relocations for more efficient processing */
-	sort_relocs(&relocs16);
 	sort_relocs(&relocs32);
 #if ELF_BITS == 64
 	sort_relocs(&relocs32neg);
 	sort_relocs(&relocs64);
+#else
+	sort_relocs(&relocs16);
 #endif
 
 	/* Print the relocations */