ARM: add renameat2 syscall

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
[dropped arch/arm/include/asm/unistd.h changes --rmk]
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

arch/arm/kernel/calls.S

@@ -391,6 +391,7 @@
 		CALL(sys_finit_module)
 /* 380 */	CALL(sys_sched_setattr)
 		CALL(sys_sched_getattr)
+		CALL(sys_renameat2)
 #ifndef syscalls_counted
 .equ syscalls_padding, ((NR_syscalls + 3) & ~3) - NR_syscalls
 #define syscalls_counted