create PX4 platform layer initialization helper (#11269)

- starts requirements for PX4 modules (hrt, param, etc)

boards/av/x-v1/src/init.c

@@ -55,7 +55,6 @@
 #include <debug.h>
 #include <errno.h>
 
-#include "platform/cxxinitialize.h"
 #include <nuttx/board.h>
 #include <nuttx/spi/spi.h>
 #include <nuttx/i2c/i2c_master.h>
@@ -75,11 +74,8 @@
 #include <drivers/drv_board_led.h>
 
 #include <systemlib/px4_macros.h>
-#include <systemlib/cpuload.h>
-#include <perf/perf_counter.h>
-#include <systemlib/err.h>
 
-#include <parameters/param.h>
+#include <px4_init.h>
 #include <px4_i2c.h>
 
 #include "up_internal.h"
@@ -209,13 +205,7 @@ stm32_boardinitialize(void)
 
 __EXPORT int board_app_initialize(uintptr_t arg)
 {
-	/* run C++ ctors before we go any further */
-	up_cxxinitialize();
-
-	/* configure the high-resolution time/callout interface */
-	hrt_init();
-
-	param_init();
+	px4_platform_init();
 
 	/* configure the DMA allocator */
 
@@ -223,11 +213,6 @@ __EXPORT int board_app_initialize(uintptr_t arg)
 		PX4_ERR("DMA alloc FAILED");
 	}
 
-	/* configure CPU load estimation */
-#ifdef CONFIG_SCHED_INSTRUMENTATION
-	cpuload_initialize_once();
-#endif
-
 	/* set up the serial DMA polling */
 	static struct hrt_call serial_dma_call;
 	struct timespec ts;