Rover: fixed GPS test (detection of uBlox needs 10Hz poll)

APMrover2/test.pde

@@ -384,7 +384,7 @@ test_gps(uint8_t argc, const Menu::arg *argv)
 	delay(1000);
 
 	while(1){
-		delay(333);
+		delay(100);
 
 		// Blink GPS LED if we don't have a fix
 		// ------------------------------------