mtd: devices: convert OMAP BCH to devm_ioremap_resource()

Convert all users of devm_request_and_ioremap() to the newly introduced
devm_ioremap_resource() which provides more consistent error handling.

Signed-off-by: Silviu-Mihai Popescu <silviupopescu1990@gmail.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>