ip: Fix command line option parsing of "ip route get ..."

I found and fixed a bug in the command line options parsing of "ip route get":
It was impossible to get any option other than the IP address
recognized correctly, and e.g. the command "ip route get connected"
just hung up infinitely in the options parsing loop instead of
printing an error message.

Signed-off-by: Christian Hornung <chhornung@googlemail.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

networking/libiproute/iproute.c

@@ -788,8 +788,8 @@ static int iproute_get(char **argv)
 				}
 				req.r.rtm_dst_len = addr.bitlen;
 			}
-			argv++;
 		}
+		argv++;
 	}
 
 	if (req.r.rtm_dst_len == 0) {