cmake remove circular linking and reorganize

- px4_add_module now requires MAIN
 - px4_add_library doesn't automatically link

src/modules/px4iofirmware/CMakeLists.txt

@@ -31,19 +31,25 @@
 #
 ############################################################################
 
-px4_add_module(
-	MODULE modules__px4iofirmware
-	SRCS
-		../systemlib/hx_stream.c
-		../systemlib/perf_counter.c
-		../systemlib/pwm_limit/pwm_limit.c
-		adc.c
-		controls.c
-		mixer.cpp
-		px4io.c
-		registers.c
-		safety.c
-		serial.c
-	DEPENDS
-		platforms__common
+add_library(px4iofirmware
+	hx_stream.c
+	../systemlib/pwm_limit/pwm_limit.c
+	adc.c
+	controls.c
+	mixer.cpp
+	px4io.c
+	registers.c
+	safety.c
+	serial.c
 	)
+
+set_property(GLOBAL APPEND PROPERTY PX4_MODULE_LIBRARIES px4iofirmware)
+target_link_libraries(px4iofirmware
+	PUBLIC
+		nuttx_apps
+		nuttx_arch
+		nuttx_c
+		mixer
+		rc
+		perf
+)