[committed] MAINTAINERS: Add myself as an aarch64 port reviewer

[Alex Coplan]

Hi,

Following on from the announcement here:
https://gcc.gnu.org/pipermail/gcc/2025-July/246267.html
adding myself as an aarch64 port reviewer.

Pushed to trunk.

Thanks,
Alex

ChangeLog:

        * MAINTAINERS (Reviewers): Add myself for the aarch64 port.

diff --git a/MAINTAINERS b/MAINTAINERS
index 5d5cfaa4e86..86387270deb 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -274,6 +274,7 @@ check in changes outside of the parts of the compiler they 
maintain.
 
                         Reviewers
 
+aarch64 port            Alex Coplan            <alex.cop...@arm.com>
 aarch64 port            Andrew Pinski          <pins...@gmail.com>
 arm port (MVE)          Christophe Lyon         <christophe.l...@arm.com>
 callgraph               Martin Jambor           <mjam...@suse.cz>