utils: relax strtoX checking in get_time_rtt

ip route change dev tap0 192.168.7.0/24 rto_min 1ms
Error: argument "1ms" is wrong: "rto_min" value is invalid

get_time_rtt() checks for 's' or 'msec' and converts to milliseconds
if needed.

Fixes: 697ac639 (utils: fix range checking for get_u32/get_u64 et all)
Signed-off-by: Florian Westphal <fw@strlen.de>

lib/utils.c

@@ -144,8 +144,8 @@ int get_time_rtt(unsigned *val, const char *arg, int *raw)
 		if (t < 0.0)
 			return -1;
 
-		/* extra non-digits */
-		if (!p || p == arg || *p)
+		/* no digits? */
+		if (!p || p == arg)
 			return -1;
 
 		/* over/underflow */
@@ -154,8 +154,8 @@ int get_time_rtt(unsigned *val, const char *arg, int *raw)
 	} else {
 		res = strtoul(arg, &p, 0);
 
-		/* empty string or trailing non-digits */
-		if (!p || p == arg || *p)
+		/* empty string? */
+		if (!p || p == arg)
 			return -1;
 
 		/* overflow */