spi: bcm-qspi: Avoid setting MSPI_CDRAM_PCS for spi-nor master

Added fix for probing of spi-nor device non-zero chip selects. Set
MSPI_CDRAM_PCS (peripheral chip select) with spi master for MSPI
controller and not for MSPI/BSPI spi-nor master controller. Ensure
setting of cs bit in chip select register on chip select change.

Fixes: fa236a7e

 ("spi: bcm-qspi: Add Broadcom MSPI driver")
Signed-off-by: Kamal Dasu <kdasu.kdev@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Cc: stable@vger.kernel.org