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/drivers/ms5611/ms5611.cpp

@@ -36,7 +36,7 @@
  * Driver for the MS5611 barometric pressure sensor connected via I2C or SPI.
  */
 
-#include <nuttx/config.h>
+#include <px4_config.h>
 
 #include <sys/types.h>
 #include <stdint.h>