ia64: Add accept4() syscall

While debugging udev > 170 failure on Debian Wheezy
(http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=648325), it appears
that the issue was in fact due to missing accept4() in ia64.

This patch simply adds accept4() to ia64.

Signed-off-by: Émeric Maschino <emeric.maschino@gmail.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
diff --git a/arch/ia64/kernel/entry.S b/arch/ia64/kernel/entry.S
index 5b31d46..1ccbe12 100644
--- a/arch/ia64/kernel/entry.S
+++ b/arch/ia64/kernel/entry.S
@@ -1779,6 +1779,7 @@
 	data8 sys_sendmmsg
 	data8 sys_process_vm_readv
 	data8 sys_process_vm_writev
+	data8 sys_accept4
 
 	.org sys_call_table + 8*NR_syscalls	// guard against failures to increase NR_syscalls
 #endif /* __IA64_ASM_PARAVIRTUALIZED_NATIVE */