aarch/vdso: include common/compiler.h before use __maybe_unused

In file included from criu/include/util-vdso.h:23:0,
                 from criu/include/kerndat.h:8,
                 from criu/lsm.c:8:
criu/arch/aarch64/include/asm/vdso.h:17:35: error: expected '=', ',', ';', 'asm' or '__attribute__' before 'aarch_vdso_symbol1'
 static const char* __maybe_unused aarch_vdso_symbol1 = "__kernel_clock_getres";
Signed-off-by: Andrei Vagin <avagin@virtuozzo.com>

criu/arch/aarch64/include/asm/vdso.h

@@ -2,6 +2,7 @@
 #define __CR_ASM_VDSO_H__
 
 #include "asm/int.h"
+#include "common/compiler.h"
 #include "asm-generic/vdso.h"
 
 /*