x86: remove compat_sys_x86_waitpid()

compat_sys_x86_waitpid() is not needed, as it takes the same parameters
(int, *int, int) as the native syscall.

Suggested-by: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Slaby <jslaby@suse.com>
Cc: x86@kernel.org
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>

arch/x86/ia32/sys_ia32.c

@@ -169,12 +169,6 @@ COMPAT_SYSCALL_DEFINE1(x86_mmap, struct mmap_arg_struct32 __user *, arg)
 			       a.offset>>PAGE_SHIFT);
 }
 
-COMPAT_SYSCALL_DEFINE3(x86_waitpid, compat_pid_t, pid, unsigned int __user *,
-		       stat_addr, int, options)
-{
-	return compat_sys_wait4(pid, stat_addr, options, NULL);
-}
-
 /* warning: next two assume little endian */
 COMPAT_SYSCALL_DEFINE5(x86_pread, unsigned int, fd, char __user *, ubuf,
 		       u32, count, u32, poslo, u32, poshi)