[PATCH v2 0/5] ARM: pxa: move gpio driver into drivers directory

[Haojian Zhuang]

Changelog:
v2:
	1. Remove gpio.c from mach-pxa & mach-mmp that is introduced from v1.
	2. Remove init function in gpio.c. Move the platfrom_device_register()
	   into platform driver.
	3. Initialize pxa_gpio_regs in gpio-pxa.c
	4. Simplify code of identifing pxa gpio series or mmp gpio series.
	5. Use linux/io.h instead of asm/io.h.