spi: cadence-quadspi: Reset CMD_CTRL Reg on cmd r/w completion

If one leaves the CQSPI_REG_CMDCTRL in an unclean state this may cause
issues in future command reads. This issue came to light when some flash
reads in STIG mode were coming back dirty.
Signed-off-by: Dhruva Gole <d-gole@ti.com>
Link: https://lore.kernel.org/r/20230125081023.1573712-2-d-gole@ti.comSigned-off-by: Mark Brown <broonie@kernel.org>

drivers/spi/spi-cadence-quadspi.c

@@ -549,6 +549,9 @@ static int cqspi_command_read(struct cqspi_flash_pdata *f_pdata,
 		memcpy(rxbuf, &reg, read_len);
 	}
 
+	/* Reset CMD_CTRL Reg once command read completes */
+	writel(0, reg_base + CQSPI_REG_CMDCTRL);
+
 	return 0;
 }
 
@@ -613,7 +616,12 @@ static int cqspi_command_write(struct cqspi_flash_pdata *f_pdata,
 		}
 	}
 
-	return cqspi_exec_flash_cmd(cqspi, reg);
+	ret = cqspi_exec_flash_cmd(cqspi, reg);
+
+	/* Reset CMD_CTRL Reg once command write completes */
+	writel(0, reg_base + CQSPI_REG_CMDCTRL);
+
+	return ret;
 }
 
 static int cqspi_read_setup(struct cqspi_flash_pdata *f_pdata,