checksyscalls: ignore -Wunused-macros

The macros defined in this file are for testing only and are purposely
not used. When compiled with W=2, both gcc and clang yield some
-Wunused-macros warnings. Ignore them.
Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

scripts/checksyscalls.sh

@@ -268,4 +268,4 @@ syscall_list() {
 }
 
 (ignore_list && syscall_list $(dirname $0)/../arch/x86/entry/syscalls/syscall_32.tbl) | \
-$* -Wno-error -E -x c - > /dev/null
+$* -Wno-error -Wno-unused-macros -E -x c - > /dev/null