MAINTAINERS: Add Vittorio to "Developers with git write access who are currently not maintaining any specific part"

Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>

MAINTAINERS

@@ -546,6 +546,7 @@ Martin Storsjö
 Panagiotis Issaris
 Pedro Arthur
 Sebastien Zwickert
+Vittorio Giovara
 wm4
 (this list is incomplete)