Use px4_config.h instead of nuttx/config.h

Modified code to use OS independent header file for config settings.

Signed-off-by: Mark Charlebois <charlebm@gmail.com>

src/modules/uORB/objects_common.cpp

@@ -41,7 +41,7 @@
  * @defgroup topics List of all uORB topics.
  */
 
-#include <nuttx/config.h>
+#include <px4_config.h>
 
 #include <drivers/drv_orb_dev.h>
 

src/modules/uORB/uORB.cpp

@@ -36,7 +36,7 @@
  * A lightweight object broker.
  */
 
-#include <nuttx/config.h>
+#include <px4_config.h>
 
 #include <drivers/device/device.h>