ARM: OMAP2+: included some headers twice

arch/arm/mach-omap2/: included some headers tiwce:
- arch/arm/mach-omap2/board-ldp.c: 'linux/gpio.h'
- arch/arm/mach-omap2/io.c: 'common.h'
- arch/arm/mach-omap2/omap_hwmod_44xx_data.c: 'plat/i2c.h'

Remove the duplicates.

Signed-off-by: Danny Kukawka <danny.kukawka@bisect.de>
Signed-off-by: Tony Lindgren <tony@atomide.com>