docs(maintainers): update NPU driver files

New files have been added for the Arm(R) Ethos(TM)-N NPU driver with the
addition of TZMP1 support so the files in the maintainers list have been
updated accordingly.

Signed-off-by: Mikael Olsson <mikael.olsson@arm.com>
Change-Id: I3768b2ab78c117c1dd4fc03b38cf35f6811fa378
diff --git a/docs/about/maintainers.rst b/docs/about/maintainers.rst
index db412f5..f36865a 100644
--- a/docs/about/maintainers.rst
+++ b/docs/about/maintainers.rst
@@ -179,6 +179,10 @@
 :|G|: `mikaelolsson-arm`_
 :|F|: drivers/arm/ethosn/
 :|F|: include/drivers/arm/ethosn.h
+:|F|: include/drivers/arm/ethosn_cert.h
+:|F|: include/drivers/arm/ethosn_fip.h
+:|F|: include/drivers/arm/ethosn_oid.h
+:|F|: plat/arm/board/juno/juno_ethosn_tzmp1_def.h
 :|F|: plat/arm/common/fconf/fconf_ethosn_getter.c
 :|F|: include/plat/arm/common/fconf_ethosn_getter.h
 :|F|: fdts/juno-ethosn.dtsi