docs(maintainers): add code owners for Firmware Update driver

Added myself and Sandrine Bailleux as code owners for Firmware
Update driver.

Signed-off-by: Manish V Badarkhe <manish.badarkhe@arm.com>
Change-Id: I34fad895c6236fedc814fb6da4b04fd7fbed9227
diff --git a/docs/about/maintainers.rst b/docs/about/maintainers.rst
index c6c3e22..d785fc2 100644
--- a/docs/about/maintainers.rst
+++ b/docs/about/maintainers.rst
@@ -319,6 +319,15 @@
 :|F|: include/drivers/measured_boot
 :|F|: plat/arm/board/fvp/fvp_measured_boot.c
 
+PSA Firmware Update
+^^^^^^^^^^^^^^^^^^^
+:|M|: Manish Badarkhe <manish.badarkhe@arm.com>
+:|G|: `ManishVB-Arm`_
+:|M|: Sandrine Bailleux <sandrine.bailleux@arm.com>
+:|G|: `sandrine-bailleux-arm`_
+:|F|: drivers/fwu
+:|F|: include/drivers/fwu
+
 System Control and Management Interface (SCMI) Server
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 :|M|: Etienne Carriere <etienne.carriere@st.com>