spi: cadence-quadspi: Add flag for direct mode writes

Create new flag inorder to avoid playing with use_direct_mode
flag currently being used throughout the driver.
Disable DAC write if auto polling is disabled or CQSPI_DISABLE_DAC_MODE
is set.

Signed-off-by: Dhruva Gole <d-gole@ti.com>
Link: https://lore.kernel.org/r/20230125081023.1573712-3-d-gole@ti.com


Signed-off-by: Mark Brown <broonie@kernel.org>