generalise Treo680 code and add support for Palm Centro - round 3

[Tomáš Čech]

Hi,

this is round 3 of generalisation Treo680 code and consequential add Palm Centro 685 support.

Changes since last round:
	- filename is now palmtreo.c to remain Palm devices consistency
	- generic functions are now beginning with treo_ (instead of previous palmgsm_)
	- pxamci_platform_data now contains also '.gpio_card_ro		= -1,'
	- added MAINTAINERS entry
	- reduced patchset (patches preceding these are already applied)

Thanks for your time.

Round 3 - fight!

Best regards,

Tomas Cech