net: strict_strtoul is obsolete, use kstrtoul instead

patch found using checkpatch.pl

Signed-off-by: Cosmin Stanescu <cosmin90stanescu@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/dns_resolver/dns_key.c b/net/dns_resolver/dns_key.c
index 0a69d07..f347a2c 100644
--- a/net/dns_resolver/dns_key.c
+++ b/net/dns_resolver/dns_key.c
@@ -118,7 +118,7 @@
 				if (opt_vlen <= 0)
 					goto bad_option_value;
 
-				ret = strict_strtoul(eq, 10, &derrno);
+				ret = kstrtoul(eq, 10, &derrno);
 				if (ret < 0)
 					goto bad_option_value;