Set flags for building the proper DriverFramework target

The DF_TARGET cmake variable needs to be set to (linux, darwin, qurt, nuttx)
The define __DF_LINUX or __DF_QURT needs to be set.
The __DF_DARWIN target is untested

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

CMakeLists.txt

@@ -150,6 +150,16 @@ list(GET config_args 1 BOARD)
 list(GET config_args 2 LABEL)
 set(target_name "${OS}-${BOARD}-${LABEL}")
 
+if("${OS}" STREQUAL "posix")
+	if (APPLE)
+		set(DF_TARGET darwin)
+	else()
+		set(DF_TARGET linux)
+	endif()
+else()
+	set(DF_TARGET ${OS})
+endif()
+
 message(STATUS "${target_name}")
 
 # switch to ros CMake file if building ros
@@ -327,6 +337,10 @@ endforeach()
 add_subdirectory(src/firmware/${OS})
 add_subdirectory(src/lib/DriverFramework)
 
+if("${OS}" STREQUAL "nuttx")
+	add_dependencies(df_driver_framework nuttx_export_${BOARD})
+endif()
+
 if (config_io_board)
 	add_subdirectory(src/modules/px4iofirmware)
 endif()