spi: bcm-qspi: Fix BSPI QUAD and DUAL mode support when using flex mode

spi: bcm-qspi: Fix BSPI QUAD and DUAL mode support when using flex mode

[ Upstream commit 79629d0f7ce5b38515c1716911a0181f01b91102 ]

Fix data transfer width settings based on DT field 'spi-rx-bus-width'
to configure BSPI in single, dual or quad mode by using data width
and not the command width.

Fixes: 5f195ee7d830c ("spi: bcm-qspi: Implement the spi_mem interface")

Signed-off-by: Rayagonda Kokatanur <rayagonda.kokatanur@broadcom.com>
Link: https://lore.kernel.org/r/1565086070-28451-1-git-send-email-rayagonda.kokatanur@broadcom.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>