DriverFramework purge

The bulk of this change was tightly coupled and needed to be deleted in one pass. Some of the smaller changes were things that broke as a result of the initial purge and subsequently fixed by further eradicating unnecessary platform differences. Finally, I deleted any dead code I came across in the related files I touched while going through everything.

 - DriverFramework (src/lib/DriverFramework submodule) completely removed
 - added dspal submodule in qurt platform (was brought in via DriverFramework)
 - all df wrapper drivers removed
 - all boards using df wrapper drivers updated to use in tree equivalents
 - unused empty arch/board.h on posix and qurt removed
 - unused IOCTLs removed (pub block, priv, etc)
 - Integrator delete methods only used from df wrapper drivers
 - commander: sensor calibration use "NuttX version" everywhere for now
 - sensors: update to px4_{open, read, close} instead of DevMgr wrapper (adc open for analog differential pressure)
 - battery_status: update to px4_{open, read, close} instead of DevMgr wrapper (adc open for analog differential pressure)
 - cdev cleanup conflicting typedefs and names with actual OS (pollevent_t, etc)
 - load_mon and top remove from linux boards (unused)
 - delete unused PX4_MAIN_FUNCTION
 - delete unused getreg32 macro
 - delete unused SIOCDEVPRIVATE define
 - named each platform tasks consistently
 - posix list_devices and list_topics removed (list_files now shows all virtual files)

boards/atlflight/excelsior/qurt.cmake

@@ -51,11 +51,6 @@ px4_add_board(
 		qshell/qurt
 		snapdragon_pwm_out
 		spektrum_rc
-	DF_DRIVERS
-		isl29501
-		ltc2946
-		mpu9250
-		trone
 	MODULES
 		airspeed_selector
 		attitude_estimator_q