gps: Fix OSS build

* Add fix from Scott/Keith for creating a forward declaration of the
   needed proprietary parts.

Change-Id: Ic958cd94b926048f4c9161884b61273bd4d93503

gps/core/UlpProxyBase.h

@@ -30,7 +30,10 @@
 #define ULP_PROXY_BASE_H
 
 #include <gps_extended.h>
-#include "fused_location_extended.h"
+
+struct FlpExtLocation_s;
+struct FlpExtBatchOptions;
+
 namespace loc_core {
 
 class LocAdapterBase;
@@ -101,7 +104,7 @@ public:
         (void)active;
         return false;
     }
-    inline virtual bool reportPositions(const FlpExtLocation* locations,
+    inline virtual bool reportPositions(const struct FlpExtLocation_s* locations,
                                         int32_t number_of_locations) {
         (void)locations;
         (void)number_of_locations;