Navio2: modify for SPI-connected GPS and fix bug in GPIO driver

src/drivers/gps/gps.cpp

@@ -374,7 +374,7 @@ int GPS::pollOrRead(uint8_t *buf, size_t buf_length, int timeout)
 {
 	handleInjectDataTopic();
 
-#ifndef __PX4_QURT
+#if !defined(__PX4_QURT) || !defined(__PX4_POSIX_RPI)
 
 	/* For non QURT, use the usual polling. */
 
@@ -807,6 +807,7 @@ GPS::task_main()
 				}
 			}
 
+#if !defined(__PX4_POSIX_RPI)
 			/* select next mode */
 			switch (_mode) {
 			case GPS_DRIVER_MODE_UBX:
@@ -824,6 +825,7 @@ GPS::task_main()
 			default:
 				break;
 			}
+#endif
 		}
 
 	}