ARM: imx: include hardware.h rather than mach/hardware.h

It moves a bunch of header files included in hardware.h and itself
from mach-imx/include/mach to mach-imx, and updates users to include
hardware.h rather than mach/hardware.h.  The files in mach-imx/devices
will need to include "../hardware.h".

Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Acked-by: Sascha Hauer <s.hauer@pengutronix.de>
Acked-by: Arnd Bergmann <arnd@arndb.de>