[nrf fromtree] drivers: mspi: mspi_dw: make pinctrl include conditional

The remainder of this driver functions when pin control is disabled,
so make the include conditional as well to fully support this case.

Signed-off-by: Daniel DeGrasse <[email protected]>
(cherry picked from commit cb31e67)

Author: danieldegrasse

drivers/mspi/mspi_dw.c

@@ -1,5 +1,6 @@
 /*
  * Copyright (c) 2024 Nordic Semiconductor ASA
+ * Copyright (c) 2025 Tenstorrent AI ULC
  *
  * SPDX-License-Identifier: Apache-2.0
  */
@@ -8,7 +9,9 @@
 
 #include <zephyr/drivers/mspi.h>
 #include <zephyr/drivers/gpio.h>
+#if defined(CONFIG_PINCTRL)
 #include <zephyr/drivers/pinctrl.h>
+#endif
 #include <zephyr/logging/log.h>
 #include <zephyr/pm/device.h>
 #include <zephyr/pm/device_runtime.h>