hwmon: (aspeed-g6-pwm-tach): Add AST2700 compatible string

Extends device tree support to include the AST2700 chip variant by
adding its compatible string to the device match table.

The AST2700 PWM/TACH hardware is compatible with the existing driver
implementation used for AST2600.

Signed-off-by: Billy Tsai <billy_tsai@aspeedtech.com>
Link: https://lore.kernel.org/r/20251120-upstream_pwm_tach-v3-2-eaa2f9b300a2@aspeedtech.com
Signed-off-by: Guenter Roeck <linux@roeck-us.net>

Author: billy-tsai

drivers/hwmon/aspeed-g6-pwm-tach.c

@@ -528,6 +528,9 @@ static const struct of_device_id aspeed_pwm_tach_match[] = {
 	{
 		.compatible = "aspeed,ast2600-pwm-tach",
 	},
+	{
+		.compatible = "aspeed,ast2700-pwm-tach",
+	},
 	{},
 };
 MODULE_DEVICE_TABLE(of, aspeed_pwm_tach_match);