[ARM] 5453/1: fix building breakage of sys_oabi-compat.c due to missing kmalloc/kfree

It seems that declarations of kmalloc/kfree are missed, explicitly
include it.
Signed-off-by: Eric Miao <eric.miao@marvell.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

arch/arm/kernel/sys_oabi-compat.c

@@ -83,6 +83,7 @@
 #include <linux/net.h>
 #include <linux/ipc.h>
 #include <linux/uaccess.h>
+#include <linux/slab.h>
 
 struct oldabi_stat64 {
 	unsigned long long st_dev;