Top level bitmap drawing code doesn't check for locked bitmaps,
only memory bitmaps to do memory drawing. Assumingly because the
driver may still be able to accelerate something. So put checks
for locked bitmaps in OGL driver in addition to memory bitmap
checks when checking to use memory drawers.

Raspberry Pi backbuffer locking was wrong when locking regions.
Allow for color size, depth and stencil sizes on Raspberry Pi.
Recent updates makes adding this include directory necessary
on Raspberry Pi.