spi: Rename SPI_OPM_RX_* to SPI_RX_*

spi: Rename SPI_OPM_RX_* to SPI_RX_*

SPI_OPM_RX_AS 	- SPI_RX_SLOW
SPI_OPM_RX_AF	- SPI_RX_FAST
SPI_OPM_RX_DOUT	- SPI_RX_DUAL
SPI_OPM_RX_QOF	- SPI_RX_QUAD

Cc: Simon Glass <[email protected]>
Cc: Michal Simek <[email protected]>
Cc: Siva Durga Prasad Paladugu <[email protected]>
Tested-by: Mugunthan V N <[email protected]>
Tested-by: Bin Meng <[email protected]>
Tested-by: Jagan Teki <[email protected]>
Reviewed-by: Bin Meng <[email protected]>
Signed-off-by: Jagan Teki <[email protected]>