MIPS: Remove unused code from arch/mips/kernel/syscall.c

The variable arg3 in _sys_sysmips() is unused.  Remove it.
Signed-off-by: David Daney <ddaney@caviumnetworks.com>
To: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/2034/Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

arch/mips/kernel/syscall.c

@@ -383,12 +383,11 @@ save_static_function(sys_sysmips);
 static int __used noinline
 _sys_sysmips(nabi_no_regargs struct pt_regs regs)
 {
-	long cmd, arg1, arg2, arg3;
+	long cmd, arg1, arg2;
 
 	cmd = regs.regs[4];
 	arg1 = regs.regs[5];
 	arg2 = regs.regs[6];
-	arg3 = regs.regs[7];
 
 	switch (cmd) {
 	case MIPS_ATOMIC_SET: