include: drivers: ptp: add missing doxygen group

add ptp_clock_interface group and put under io_interfaces

Signed-off-by: Benjamin Cabé <[email protected]>

Author: kartben

include/zephyr/drivers/ptp_clock.h

@@ -7,6 +7,13 @@
 #ifndef ZEPHYR_INCLUDE_DRIVERS_PTP_CLOCK_H_
 #define ZEPHYR_INCLUDE_DRIVERS_PTP_CLOCK_H_
 
+/**
+ * @brief PTP Clock Interface
+ * @defgroup ptp_clock_interface PTP Clock Interface
+ * @ingroup io_interfaces
+ * @{
+ */
+
 #include <zephyr/kernel.h>
 #include <stdint.h>
 #include <zephyr/device.h>
@@ -103,4 +110,8 @@ static inline int ptp_clock_rate_adjust(const struct device *dev, double rate)
 
 #include <zephyr/syscalls/ptp_clock.h>
 
+/**
+ * @}
+ */
+
 #endif /* ZEPHYR_INCLUDE_DRIVERS_PTP_CLOCK_H_ */