.mailmap: update aliases for Nicolai Hähnle

Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/1999>
diff --git a/.mailmap b/.mailmap
index 2566ad7..7a071bf 100644
--- a/.mailmap
+++ b/.mailmap
@@ -447,10 +447,10 @@
 
 Nick Sarnie <commendsarnex@gmail.com>
 
+Nicolai Hähnle <nicolai.haehnle@amd.com>
 Nicolai Hähnle <nicolai.haehnle@amd.com> <nhaehnle@gmail.com>
-Nicolai Hähnle <nicolai.haehnle@amd.com> Nicolai Haehnle <nhaehnle@gmail.com>
-Nicolai Hähnle <nicolai.haehnle@amd.com> Nicolai Haehnle <prefect_@gmx.net>
-Nicolai Hähnle <nicolai.haehnle@amd.com> Nicolai Haehnle <prefect@upb.de>
+Nicolai Hähnle <nicolai.haehnle@amd.com> <prefect_@gmx.net>
+Nicolai Hähnle <nicolai.haehnle@amd.com> <prefect@upb.de>
 
 Nigel Stewart <nigels@users.sourceforge.net> <nigels@sourceforge.net>
 Nigel Stewart <nigels@users.sourceforge.net> <nstewart@nvidia.com>