msm_fb..  the 'f' is for fail

What the driver calls RGBA is actually ARGB.  So advertise the correct
fb var settings to userspace so you don't confuse xorg which is actually
naive enough to believe what the driver says.  Changing to
CONFIG_FB_MSM_DEFAULT_DEPTH_ARGB8888=y doesn't actually work because
then the driver actually sets the hw up for RGBA.  This hack makes
things work while minimizing the amount of time I have to spend looking
at fbdev driver code.