This change implements BSPI driver for Broadcom BRCMSTB, NS2,
NSP SoCs works in combination with the MSPI controller driver
and implements flash read acceleration and implements the
spi_flash_read() method. Both MSPI and BSPI controllers are
needed to access spi-nor flash.
Signed-off-by: Kamal Dasu <kdasu.kdev@gmail.com> Signed-off-by: Yendapally Reddy Dhananjaya Reddy <yendapally.reddy@broadcom.com> Signed-off-by: Mark Brown <broonie@kernel.org>