[rbp] Fix for orientation handling of Pi textures

There were a number of "off by one" errors in the orientations when using accelerated jpeg<->textures on the Pi.
This mostly worked out, but was the root cause of this issue:
http://forum.xbmc.org/showthread.php?tid=192380&pid=1805144#pid1805144
Merge pull request #5555 from popcornmix/jpeg_orient

[rbp] Fix for orientation handling of Pi textures