MAINTAINERS: add yangbolu1991 as maintainer for PTP Clock

I once worked as maintainer for Linux PTP VIRTUAL CLOCK SUPPORT
and FREESCALE QORIQ PTP CLOCK DRIVER.

Although I haven't been working on zephyr PTP for long, I have
clear understanding for current zephyr PTP clock and PTP/gPTP stack.
And started to contribute for it.

Signed-off-by: Yangbo Lu <yangbo.lu@nxp.com>

Author: yangbolu1991

MAINTAINERS.yml

@@ -1995,7 +1995,9 @@ Release Notes:
     - sample.drivers.espi.ps2
 
 "Drivers: PTP Clock":
-  status: odd fixes
+  status: maintained
+  maintainers:
+    - yangbolu1991
   files:
     - drivers/ptp_clock/
     - include/zephyr/drivers/ptp_clock.h