HAL_PX4: fixed FMUv1 build

libraries/AP_HAL_PX4/Util.cpp

@@ -236,11 +236,19 @@ extern "C" {
 */
 void *PX4Util::dma_allocate(size_t size)
 {
+#ifndef CONFIG_ARCH_BOARD_PX4FMU_V1
     return fat_dma_alloc(size);
+#else
+    return malloc(size);
+#endif
 }
 void PX4Util::dma_free(void *ptr, size_t size)
 {
+#ifndef CONFIG_ARCH_BOARD_PX4FMU_V1
     fat_dma_free(ptr, size);
+#else
+    return free(ptr);
+#endif
 }
 
 #endif // CONFIG_HAL_BOARD == HAL_BOARD_PX4