s390: fold execve_tail() into start_thread(), convert to generic sys_execve()

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/arch/s390/kernel/compat_wrapper.S b/arch/s390/kernel/compat_wrapper.S
index 2d82cfc..cf1d60f 100644
--- a/arch/s390/kernel/compat_wrapper.S
+++ b/arch/s390/kernel/compat_wrapper.S
@@ -1576,7 +1576,7 @@
 	llgtr	%r2,%r2			# char *
 	llgtr	%r3,%r3			# compat_uptr_t *
 	llgtr	%r4,%r4			# compat_uptr_t *
-	jg	sys32_execve		# branch to system call
+	jg	compat_sys_execve	# branch to system call
 
 ENTRY(sys_fanotify_init_wrapper)
 	llgfr	%r2,%r2			# unsigned int