spi: zynq-qspi: Keep the bitfields naming consistent

Most of the bits/bitfields #define'd in this driver are composed with:
1/ the driver prefix
2/ the name of the register they apply to

Keep the naming consistent by applying this rule to the CONFIG register
internals. These definitions will be used in a following change set.
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/r/20191108140744.1734-4-miquel.raynal@bootlin.comSigned-off-by: Mark Brown <broonie@kernel.org>

drivers/spi/spi-zynq-qspi.c

@@ -60,9 +60,9 @@
  * These are the values used in the calculation of baud rate divisor and
  * setting the slave select.
  */
-#define ZYNQ_QSPI_BAUD_DIV_MAX		GENMASK(2, 0) /* Baud rate maximum */
-#define ZYNQ_QSPI_BAUD_DIV_SHIFT	3 /* Baud rate divisor shift in CR */
-#define ZYNQ_QSPI_SS_SHIFT		10 /* Slave Select field shift in CR */
+#define ZYNQ_QSPI_CONFIG_BAUD_DIV_MAX	GENMASK(2, 0) /* Baud rate maximum */
+#define ZYNQ_QSPI_CONFIG_BAUD_DIV_SHIFT	3 /* Baud rate divisor shift */
+#define ZYNQ_QSPI_CONFIG_PCS		10 /* Peripheral Chip Select */
 
 /*
  * QSPI Interrupt Registers bit Masks
@@ -292,7 +292,7 @@ static void zynq_qspi_chipselect(struct spi_device *spi, bool assert)
 		/* Select the slave */
 		config_reg &= ~ZYNQ_QSPI_CONFIG_SSCTRL_MASK;
 		config_reg |= (((~(BIT(spi->chip_select))) <<
-				ZYNQ_QSPI_SS_SHIFT) &
+				ZYNQ_QSPI_CONFIG_PCS) &
 				ZYNQ_QSPI_CONFIG_SSCTRL_MASK);
 	} else {
 		config_reg |= ZYNQ_QSPI_CONFIG_SSCTRL_MASK;
@@ -331,7 +331,7 @@ static int zynq_qspi_config_op(struct zynq_qspi *xqspi, struct spi_device *spi)
 	 *      ----------------
 	 *      111 - divide by 256
 	 */
-	while ((baud_rate_val < ZYNQ_QSPI_BAUD_DIV_MAX)  &&
+	while ((baud_rate_val < ZYNQ_QSPI_CONFIG_BAUD_DIV_MAX)  &&
 	       (clk_get_rate(xqspi->refclk) / (2 << baud_rate_val)) >
 		spi->max_speed_hz)
 		baud_rate_val++;
@@ -347,7 +347,7 @@ static int zynq_qspi_config_op(struct zynq_qspi *xqspi, struct spi_device *spi)
 		config_reg |= ZYNQ_QSPI_CONFIG_CPOL_MASK;
 
 	config_reg &= ~ZYNQ_QSPI_CONFIG_BDRATE_MASK;
-	config_reg |= (baud_rate_val << ZYNQ_QSPI_BAUD_DIV_SHIFT);
+	config_reg |= (baud_rate_val << ZYNQ_QSPI_CONFIG_BAUD_DIV_SHIFT);
 	zynq_qspi_write(xqspi, ZYNQ_QSPI_CONFIG_OFFSET, config_reg);
 
 	return 0;