MAINTAINERS: Update email of Stefano Babic

Replace my old e-mail with the current one to get still involved in the
project.

Signed-off-by: Stefano Babic <sbabic@nabladev.com>
diff --git a/doc/git-mailrc b/doc/git-mailrc
index 1177e42..6214dae 100644
--- a/doc/git-mailrc
+++ b/doc/git-mailrc
@@ -42,7 +42,7 @@
 alias monstr         Michal Simek <monstr@monstr.eu>
 alias prom           Minkyu Kang <mk7.kang@samsung.com>
 alias ptomsich       Philipp Tomsich <philipp.tomsich@theobroma-systems.com>
-alias sbabic         Stefano Babic <sbabic@denx.de>
+alias sbabic         Stefano Babic <sbabic@nabladev.com>
 alias simongoldschmidt Simon Goldschmidt <simon.k.r.goldschmidt@gmail.com>
 alias sjg            Simon Glass <sjg@chromium.org>
 alias smcnutt        Scott McNutt <smcnutt@psyent.com>