dt-bindings: clock: imx8mq: Add SNVS clock

Add macro for the SNVS clock of the i.MX8MQ.
Signed-off-by: Anson Huang <Anson.Huang@nxp.com>
Reviewed-by: Leonard Crestez <leonard.crestez@nxp.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>

include/dt-bindings/clock/imx8mq-clock.h

@@ -400,5 +400,7 @@
 #define IMX8MQ_CLK_GPIO4_ROOT			262
 #define IMX8MQ_CLK_GPIO5_ROOT			263
 
-#define IMX8MQ_CLK_END				264
+#define IMX8MQ_CLK_SNVS_ROOT			264
+
+#define IMX8MQ_CLK_END				265
 #endif /* __DT_BINDINGS_CLOCK_IMX8MQ_H */