introduced by: 96974a24
(omap: consolidate touch screen initialization among different boards)

ads7846 driver can use either gpio_pendown or get_pendown_state()
callback. In case of gpio_pendown, it requests the provided gpio_pendown
thus resulting in double requesting that gpio:

ads7846 spi1.0: failed to request pendown GPIO57
ads7846: probe of spi1.0 failed with error -16

Fix this by restricting the gpio request to the case of
get_pendown_state() callback is used.
Signed-off-by: NIgor Grinberg <grinberg@compulab.co.il>
Tested-by: NThomas Weber <weber@corscience.de>
Signed-off-by: NTony Lindgren <tony@atomide.com>

and reduce amount of copy/paste
Signed-off-by: NMike Rapoport <mike@compulab.co.il>
CC: Oleg Drokin <green@linuxhacker.ru>
Signed-off-by: NTony Lindgren <tony@atomide.com>

Introduce omap_pmic_init that registers i2c bus and PMIC device on that
bus and add omap2/3/4 wrappers for common cases.
Signed-off-by: NMike Rapoport <mike@compulab.co.il>
Signed-off-by: NTony Lindgren <tony@atomide.com>

Add common-board-devices.c that will contain the code for peripheral
devices initializatoin shared between multiple boards.
Start small with touchscreen initialization.
Signed-off-by: NMike Rapoport <mike@compulab.co.il>
Signed-off-by: NTony Lindgren <tony@atomide.com>