docs(gpt): add documentation page for GPT library

This patch adds some documentation for the GPT library as well as adds
code owners for it.

Signed-off-by: John Powell <john.powell@arm.com>
Change-Id: If1cd79626eadb27e1024d731b26ee2e20af74a66
diff --git a/docs/about/maintainers.rst b/docs/about/maintainers.rst
index 337dde6..7a48601 100644
--- a/docs/about/maintainers.rst
+++ b/docs/about/maintainers.rst
@@ -75,7 +75,7 @@
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 :|M|: Mark Dykes <mark.dykes@arm.com>
 :|G|: `mardyk01`_
-:|M|: John Powell <John.Powell@arm.com>
+:|M|: John Powell <john.powell@arm.com>
 :|G|: `john-powell-arm`_
 :|F|: services/std_svc/sdei/
 
@@ -105,7 +105,7 @@
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 :|M|: Manish Badarkhe <manish.badarkhe@arm.com>
 :|G|: `ManishVB-Arm`_
-:|M|: John Powell <John.Powell@arm.com>
+:|M|: John Powell <john.powell@arm.com>
 :|G|: `john-powell-arm`_
 :|F|: bl31/ehf.c
 
@@ -115,7 +115,7 @@
 :|G|: `bipinravi-arm`_
 :|M|: Mark Dykes <mark.dykes@arm.com>
 :|G|: `mardyk01`_
-:|M|: John Powell <John.Powell@arm.com>
+:|M|: John Powell <john.powell@arm.com>
 :|G|: `john-powell-arm`_
 :|M|: Zelalem Aweke <Zelalem.Aweke@arm.com>
 :|G|: `zelalem-aweke`_
@@ -201,7 +201,7 @@
 ^^^^^^^^^^^^^^^^^
 :|M|: Lauren Wehrmeister <Lauren.Wehrmeister@arm.com>
 :|G|: `laurenw-arm`_
-:|M|: John Powell <John.Powell@arm.com>
+:|M|: John Powell <john.powell@arm.com>
 :|G|: `john-powell-arm`_
 :|F|: lib/cpus/
 
@@ -255,7 +255,7 @@
 ^^^^^^^^^^^^^^^^^^
 :|M|: Alexei Fedorov <Alexei.Fedorov@arm.com>
 :|G|: `AlexeiFedorov`_
-:|M|: John Powell <John.Powell@arm.com>
+:|M|: John Powell <john.powell@arm.com>
 :|G|: `john-powell-arm`_
 :|F|: lib/libc/
 
@@ -335,6 +335,15 @@
 :|F|: include/lib/mpmm/
 :|F|: lib/mpmm/
 
+Granule Protection Tables Library (GPT-RME)
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+:|M|: Mark Dykes <mark.dykes@arm.com>
+:|G|: `mardyk01`_
+:|M|: John Powell <john.powell@arm.com>
+:|G|: `john-powell-arm`_
+:|F|: lib/gpt_rme
+:|F|: include/lib/gpt_rme
+
 Platform Ports
 ~~~~~~~~~~~~~~