resources: Add register address resource type

Currently a bunch of I2C/SPI MFD drivers are using IORESOURCE_IO for
register address ranges. Since this causes some confusion due to the
primary use of this resource type for PCI/ISA I/O ports create a new
resource type IORESOURCE_REG.

Unfortunately the current resource types are specified as bitmasks and
there are no free bitmasks even though they really shouldn't be used as
such so we define the new type as IORESOURCE_IO | IORESOURCE_MEM.
Benjamin Herrenschmidt and Russell King have both verified that none of
the users in this series will have a problem with this, and no new code
should be affected.

This patch was written by Russell King but he found himself unable to
take the patch further.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Haojian Zhuang <haojian.zhuang@gmail.com>
Tested-by: Haojian Zhuang <haojian.zhuang@gmail.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>