pinctrl: aspeed: Describe the heartbeat function on ball Y23

The default pinmux configuration for Y23 is to route a heartbeat to
drive a LED. Previous revisions of the AST2600 datasheet did not include
a description of this function.

Fixes: 2eda1cdec49f ("pinctrl: aspeed: Add AST2600 pinmux support")
Signed-off-by: Andrew Jeffery <[e-mail]>
Signed-off-by: Joel Stanley <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Linus Walleij <[e-mail]>

drivers/pinctrl/aspeed/pinctrl-aspeed-g6.c

···
 #define SCU634		0x634 /* Disable GPIO Internal Pull-Down #5 */
 #define SCU638		0x638 /* Disable GPIO Internal Pull-Down #6 */
 #define SCU694		0x694 /* Multi-function Pin Control #25 */
+#define SCU69C		0x69C /* Multi-function Pin Control #27 */
 #define SCUC20		0xC20 /* PCIE configuration Setting Control */
 
 #define ASPEED_G6_NR_PINS 256
···
 #define Y23 127
 SIG_EXPR_LIST_DECL_SEMG(Y23, PWM15, PWM15G1, PWM15, SIG_DESC_SET(SCU41C, 31));
 SIG_EXPR_LIST_DECL_SESG(Y23, THRUOUT3, THRU3, SIG_DESC_SET(SCU4BC, 31));
-PIN_DECL_2(Y23, GPIOP7, PWM15, THRUOUT3);
+SIG_EXPR_LIST_DECL_SESG(Y23, HEARTBEAT, HEARTBEAT, SIG_DESC_SET(SCU69C, 31));
+PIN_DECL_3(Y23, GPIOP7, PWM15, THRUOUT3, HEARTBEAT);
 GROUP_DECL(PWM15G1, Y23);
 FUNC_DECL_2(PWM15, PWM15G0, PWM15G1);
 
 FUNC_GROUP_DECL(THRU3, AB24, Y23);
+FUNC_GROUP_DECL(HEARTBEAT, Y23);
 
 #define AA25 128
 SSSF_PIN_DECL(AA25, GPIOQ0, TACH0, SIG_DESC_SET(SCU430, 0));
···
 	ASPEED_PINCTRL_GROUP(GPIU5),
 	ASPEED_PINCTRL_GROUP(GPIU6),
 	ASPEED_PINCTRL_GROUP(GPIU7),
+	ASPEED_PINCTRL_GROUP(HEARTBEAT),
 	ASPEED_PINCTRL_GROUP(HVI3C3),
 	ASPEED_PINCTRL_GROUP(HVI3C4),
 	ASPEED_PINCTRL_GROUP(I2C1),
···
 	ASPEED_PINCTRL_FUNC(GPIU5),
 	ASPEED_PINCTRL_FUNC(GPIU6),
 	ASPEED_PINCTRL_FUNC(GPIU7),
+	ASPEED_PINCTRL_FUNC(HEARTBEAT),
 	ASPEED_PINCTRL_FUNC(I2C1),
 	ASPEED_PINCTRL_FUNC(I2C10),
 	ASPEED_PINCTRL_FUNC(I2C11),