.mailmap: add an alias for Alexandros Frantzis

Reviewed-by: Alexandros Frantzis <alexandros.frantzis@collabora.com>
diff --git a/.mailmap b/.mailmap
index a31a817..cb8a27b 100644
--- a/.mailmap
+++ b/.mailmap
@@ -26,6 +26,8 @@
 
 Alexander von Gluck IV <kallisti5@unixzen.com> Alexander von Gluck <kallisti5@unixzen.com>
 
+Alexandros Frantzis <alexandros.frantzis@collabora.com> <Alexandros.Frantzis@canonical.com>
+
 Alex Corscadden <alexc@vmware.com> <alexc@alexc-dev1.prom.eng.vmware.com>
 Alex Corscadden <alexc@vmware.com> <alexc@alexc-dev1.vmware.com>