spi: atmel-quadspi: Fix warning in doc-comment

The doc-comment for `struct atmel_qspi_pcal` had a typo in one of the
struct members' name, causing a warning with the `W=1` option.

Fixes: 5af4220 ("spi: atmel-quadspi: Add support for sama7g5 QSPI")
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202501311707.Ltj0qXse-lkp@intel.com/
Signed-off-by: Bence Csókás <csokas.bence@prolan.hu>
Link: https://patch.msgid.link/20250203151249.79876-2-csokas.bence@prolan.hu
Signed-off-by: Mark Brown <broonie@kernel.org>

Author: Bence Csókás

drivers/spi/atmel-quadspi.c

@@ -235,8 +235,8 @@
 /**
  * struct atmel_qspi_pcal - Pad Calibration Clock Division
  * @pclk_rate: peripheral clock rate.
- * @pclkdiv: calibration clock division. The clock applied to the calibration
- *           cell is divided by pclkdiv + 1.
+ * @pclk_div: calibration clock division. The clock applied to the calibration
+ *           cell is divided by pclk_div + 1.
  */
 struct atmel_qspi_pcal {
 	u32 pclk_rate;