Use generic compat_sys_wait4 to implement 32-bit wait4(2).

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
diff --git a/arch/mips/kernel/scall64-o32.S b/arch/mips/kernel/scall64-o32.S
index 739f399..271b2cb 100644
--- a/arch/mips/kernel/scall64-o32.S
+++ b/arch/mips/kernel/scall64-o32.S
@@ -316,7 +316,7 @@
 	PTR	sys_vhangup
 	PTR	sys_ni_syscall			/* was sys_idle	 */
 	PTR	sys_ni_syscall			/* sys_vm86 */
-	PTR	sys32_wait4
+	PTR	compat_sys_wait4
 	PTR	sys_swapoff			/* 4115 */
 	PTR	sys32_sysinfo
 	PTR	sys32_ipc