ARM: palmtreo: fix lcd initilialization on treo680

ARM: palmtreo: fix lcd initilialization on treo680

This patch gets the LCD working on my Palm Treo680 by adding some code that
manages the three gpios interfaced to the lcd on the Treo 680.  The precise role
of each gpio in the hardware architecture is not entirely clear to me; this
patch is the result of trial-and-error and observing how the PalmOS code
initializes the lcd.

The need for this patch is not evident when Linux is loaded from PalmOS, because
at that point the lcd-related gpios have already been configured.  But when
booting the kernel by other means, this patch is required unless the bootloader
has performed the necessary initialializations.

Signed-off-by: Mike Dunn <mikedunn@newsguy.com>
Acked-by: Tomas Cech <sleep_walker@suse.cz>
Signed-off-by: Haojian Zhuang <haojian.zhuang@gmail.com>