maintainers: Update ARM arch maintainer

Updates the ARM arch maintainer as per TSC vote 16 Feb 2022.

Signed-off-by: Kevin Townsend <[email protected]>

Author: microbuilder

MAINTAINERS.yml

@@ -129,7 +129,7 @@ ARC arch:
 ARM arch:
     status: maintained
     maintainers:
-        - ioannisg
+        - microbuilder
     collaborators:
         - carlocaione
         - galak