The accelerometer to Xorg orientation mapping had left and right
inverted, causing the output to flip opposite the desired direction when
used sideways.
This ensures that if rot8 starts while the window server output is
rotated, but the physical device is in a "normal" position, rot8 will
detect the initial misalignment and rotate the window server's output to
reflect the device's physical state.
This scenario occurs if you frequently toggle rot8 on and off as form of
rotation lock, and you:
1. Use rot8 to rotate the output sideways
2. Turn rot8 off
3. Move the physical device back into a "normal" position
4. Turn rot8 back on
