wavegain: show correct maintainer

lib/maintainers.nix

···
   rickynils = "Rickard Nilsson <[e-mail]>";
   rob = "Rob Vermaas <[e-mail]>";
   robberer = "Longrin Wischnewski <[e-mail]>";
+  robbinch = "Robbin C. <[e-mail]>";
   roconnor = "Russell O'Connor <[e-mail]>";
   roelof = "Roelof Wobben <[e-mail]>";
   romildo = "José Romildo Malaquias <[e-mail]>";

pkgs/applications/audio/wavegain/default.nix

···
     homepage = https://github.com/MestreLion/wavegain;
     license = stdenv.lib.licenses.lgpl21;
     platforms = stdenv.lib.platforms.linux;
-    maintainers = [ stdenv.lib.maintainers.devhell ];
+    maintainers = [ stdenv.lib.maintainers.robbinch ];
   };
 }