AP_GPS: remove tabs and fix coding style

libraries/AP_GPS/AP_GPS_SIRF.cpp

@@ -204,8 +204,7 @@ AP_GPS_SIRF::_accumulate(uint8_t val)
 /*
   detect a SIRF GPS
  */
-bool
-AP_GPS_SIRF::_detect(struct SIRF_detect_state &state, uint8_t data)
+bool AP_GPS_SIRF::_detect(struct SIRF_detect_state &state, uint8_t data)
 {
     switch (state.step) {
     case 1:
@@ -232,8 +231,9 @@ AP_GPS_SIRF::_detect(struct SIRF_detect_state &state, uint8_t data)
         break;
     case 4:
         state.checksum = (state.checksum + data) & 0x7fff;
-		if (++state.payload_counter == state.payload_length)
+        if (++state.payload_counter == state.payload_length) {
             state.step++;
+        }
         break;
     case 5:
         state.step++;