param: Remove unncessary else branch

Better diff with the --ignore-all-space option.

bin/varnishd/mgt/mgt_param_tweak.c

@@ -685,9 +685,9 @@ tweak_generic_bits(struct vsb *vsb, const struct parspec *par, const char *arg,
 		    desc, sign));
 	}
 
-	if (arg != NULL && arg != JSON_FMT) {
+	if (arg != NULL && arg != JSON_FMT)
 		return (bit_tweak(vsb, p, l, arg, tags, desc, sign));
-	} else {
+
 	if (arg == JSON_FMT)
 		VSB_putc(vsb, '"');
 	s = "";
@@ -701,7 +701,6 @@ tweak_generic_bits(struct vsb *vsb, const struct parspec *par, const char *arg,
 		VSB_cat(vsb, sign == '+' ? "none" : "all");
 	if (arg == JSON_FMT)
 		VSB_putc(vsb, '"');
-	}
 	return (0);
 }