MIPS: Set ENOSYS to errno on illegal system call number for syscall(2)

Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

arch/mips/kernel/scall32-o32.S

@@ -293,7 +293,7 @@ bad_alignment:
 	jr	t2
 	/* Unreached */
 
-einval:	li	v0, -EINVAL
+einval:	li	v0, -ENOSYS
 	jr	ra
 	END(sys_syscall)