linux-user: Handle ERFKILL and EHWPOISON

With definitions for generic, alpha and mips taken from 4.9-rc2.

Signed-off-by: Richard Henderson <rth@twiddle.net>
diff --git a/linux-user/syscall.c b/linux-user/syscall.c
index acb004f..11a311f 100644
--- a/linux-user/syscall.c
+++ b/linux-user/syscall.c
@@ -798,6 +798,12 @@
 #ifdef ENOMSG
     [ENOMSG]            = TARGET_ENOMSG,
 #endif
+#ifdef ERKFILL
+    [ERFKILL]           = TARGET_ERFKILL,
+#endif
+#ifdef EHWPOISON
+    [EHWPOISON]         = TARGET_EHWPOISON,
+#endif
 };
 
 static inline int host_to_target_errno(int err)