PCI: stm32: Don't use 'proxy' headers

Update header inclusions to follow IWYU (Include What You Use)
principle.

In particular, replace of_gpio.h, which is subject to removal by the
GPIOLIB subsystem, with the respective headers that are being used by the
driver.

Signed-off-by: Andy Shevchenko <[e-mail]>
Signed-off-by: Manivannan Sadhasivam <[e-mail]>
Signed-off-by: Bjorn Helgaas <[e-mail]>
Link: https://patch.msgid.link/[e-mail]

drivers/pci/controller/dwc/pcie-stm32-ep.c

···
  */
 
 #include <linux/clk.h>
+#include <linux/gpio/consumer.h>
 #include <linux/mfd/syscon.h>
 #include <linux/of_platform.h>
-#include <linux/of_gpio.h>
 #include <linux/phy/phy.h>
 #include <linux/platform_device.h>
 #include <linux/pm_runtime.h>

drivers/pci/controller/dwc/pcie-stm32.c

···
  */
 
 #include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/err.h>
+#include <linux/gpio/consumer.h>
+#include <linux/irq.h>
 #include <linux/mfd/syscon.h>
+#include <linux/mod_devicetable.h>
+#include <linux/module.h>
+#include <linux/of.h>
 #include <linux/of_platform.h>
 #include <linux/phy/phy.h>
 #include <linux/pinctrl/consumer.h>
 #include <linux/platform_device.h>
+#include <linux/pm.h>
 #include <linux/pm_runtime.h>
 #include <linux/pm_wakeirq.h>
 #include <linux/regmap.h>
 #include <linux/reset.h>
+#include <linux/stddef.h>
+
+#include "../../pci.h"
+
 #include "pcie-designware.h"
 #include "pcie-stm32.h"
-#include "../../pci.h"
 
 struct stm32_pcie {
 	struct dw_pcie pci;

drivers/pci/controller/dwc/pcie-stm32.h

···
  * Author: Christian Bruel <[e-mail]>
  */
 
+#include <linux/bits.h>
+#include <linux/device.h>
+
 #define to_stm32_pcie(x)	dev_get_drvdata((x)->dev)
 
 #define STM32MP25_PCIECR_TYPE_MASK	GENMASK(11, 8)