Added conditional statement to disable the virtualTabletJoystick output if a real joystick is connected and enabled. Without this, two different sets of values would be sent and would appear highly sporadic.

This reverts commit bf31c808.

Allows QGC to run on Raspberry Pi 2 with direct framebuffer (X/startx
not needed). Memory split seems to need 128 for GPU. Qt5 needs to be
configured with "-opengl es2 -qpa eglfs -device linux-rasp-pi2-g++".

Selected flight mode is controller by firmware. Use selecting flight
mode cannot set the check, or it will be wrong if firmware declines
change.