broadsheetfb: add multiple panel type support

Update broadsheetfb to add support for multiple panel types.  The 3.7" and
6" are known to work but the 9.7" is untested due to lack of hardware.

Signed-off-by: Jaya Kumar <jayakumar.lkml@gmail.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Krzysztof Helt <krzysztof.h1@wp.pl>
Cc: Russell King <rmk@arm.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>