pinctrl: Add pingroup and define PINCTRL_PINGROUP

Add 'struct pingroup' to represent pingroup and 'PINCTRL_PINGROUP'
macro for inline use. Both are used to manage and represent
larger number of pingroups.
Signed-off-by: Basavaraj Natikar <Basavaraj.Natikar@amd.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20220601152900.1012813-2-Basavaraj.Natikar@amd.comSigned-off-by: Linus Walleij <linus.walleij@linaro.org>

include/linux/pinctrl/pinctrl.h

@@ -26,6 +26,26 @@ struct pin_config_item;
 struct gpio_chip;
 struct device_node;
 
+/**
+ * struct pingroup - provides information on pingroup
+ * @name: a name for pingroup
+ * @pins: an array of pins in the pingroup
+ * @npins: number of pins in the pingroup
+ */
+struct pingroup {
+	const char *name;
+	const unsigned int *pins;
+	size_t npins;
+};
+
+/* Convenience macro to define a single named or anonymous pingroup */
+#define PINCTRL_PINGROUP(_name, _pins, _npins)	\
+(struct pingroup){				\
+	.name = _name,				\
+	.pins = _pins,				\
+	.npins = _npins,			\
+}
+
 /**
  * struct pinctrl_pin_desc - boards/machines provide information on their
  * pins, pads or other muxable units in this struct