AP_RPM: use HAL_EFI_ENABLED

libraries/AP_RPM/AP_RPM.cpp

@@ -121,7 +121,7 @@ void AP_RPM::init(void)
             drivers[i] = new AP_RPM_Pin(*this, i, state[i]);
         }
 #endif
-#if EFI_ENABLED
+#if HAL_EFI_ENABLED
         if (type == RPM_TYPE_EFI) {
             drivers[i] = new AP_RPM_EFI(*this, i, state[i]);
         }

libraries/AP_RPM/RPM_EFI.cpp

@@ -17,7 +17,7 @@
 
 #include "RPM_EFI.h"
 
-#if EFI_ENABLED
+#if HAL_EFI_ENABLED
 extern const AP_HAL::HAL& hal;
 
 /* 
@@ -41,4 +41,4 @@ void AP_RPM_EFI::update(void)
     state.last_reading_ms = AP_HAL::millis();
 }
 
-#endif // EFI_ENABLED
+#endif // HAL_EFI_ENABLED