MIPS: sysmips: Rewrite to use SYSCALL_DEFINE3().

Thanks to current_pt_regs() there is no need to use the dark MIPS magic.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

arch/mips/kernel/syscall.c

@@ -138,10 +138,10 @@ SYSCALL_DEFINE1(set_thread_area, unsigned long, addr)
 	return 0;
 }
 
-static inline int mips_atomic_set(struct pt_regs *regs,
-	unsigned long addr, unsigned long new)
+static inline int mips_atomic_set(unsigned long addr, unsigned long new)
 {
 	unsigned long old, tmp;
+	struct pt_regs *regs;
 	unsigned int err;
 
 	if (unlikely(addr & 3))
@@ -222,6 +222,7 @@ static inline int mips_atomic_set(struct pt_regs *regs,
 	if (unlikely(err))
 		return err;
 
+	regs = current_pt_regs();
 	regs->regs[2] = old;
 	regs->regs[7] = 0;	/* No error */
 
@@ -238,19 +239,11 @@ static inline int mips_atomic_set(struct pt_regs *regs,
 	unreachable();
 }
 
-save_static_function(sys_sysmips);
-static int __used noinline
-_sys_sysmips(nabi_no_regargs struct pt_regs regs)
+SYSCALL_DEFINE3(sysmips, long, cmd, long, arg1, long, arg2)
 {
-	long cmd, arg1, arg2;
-
-	cmd = regs.regs[4];
-	arg1 = regs.regs[5];
-	arg2 = regs.regs[6];
-
 	switch (cmd) {
 	case MIPS_ATOMIC_SET:
-		return mips_atomic_set(&regs, arg1, arg2);
+		return mips_atomic_set(arg1, arg2);
 
 	case MIPS_FIXADE:
 		if (arg1 & ~3)