pinctrl: add stubs for OF-specific pinconf functions

Allow building drivers using these interfaces with COMPILE_TEST enabled
and OF disabled by providing stub definitions.

Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202505072245.OgSXI1hh-lkp@intel.com/
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Link: https://lore.kernel.org/20250507143551.47056-1-brgl@bgdev.pl
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

Author: Bartosz Golaszewski

drivers/pinctrl/pinconf.h

@@ -142,4 +142,21 @@ int pinconf_generic_parse_dt_config(struct device_node *np,
 int pinconf_generic_parse_dt_pinmux(struct device_node *np, struct device *dev,
 				    unsigned int **pid, unsigned int **pmux,
 				    unsigned int *npins);
+#else
+static inline int
+pinconf_generic_parse_dt_config(struct device_node *np,
+				struct pinctrl_dev *pctldev,
+				unsigned long **configs,
+				unsigned int *nconfigs)
+{
+	return -ENOTSUPP;
+}
+
+static inline int
+pinconf_generic_parse_dt_pinmux(struct device_node *np, struct device *dev,
+				unsigned int **pid, unsigned int **pmux,
+				unsigned int *npins)
+{
+	return -ENOTSUPP;
+}
 #endif