change keybinding for changing browse mode

I shouldn't do that, but the old one will be much better for
choosing whether songs in browser have to be sorted by names
or modification date. Besides, binding this to browser key
makes browser behaviour more "compatible" with media library.

src/ncmpcpp.cpp

@@ -1808,12 +1808,6 @@ int main(int argc, char *argv[])
 				if (number && Mpd.AddRandomSongs(number))
 					ShowMessage("%zu random song%s added to playlist!", number, number == 1 ? "" : "s");
 			}
-#			ifndef WIN32
-			else if (myScreen == myBrowser)
-			{
-				myBrowser->ChangeBrowseMode();
-			}
-#			endif // !WIN32
 			else if (myScreen->ActiveWindow() == myLibrary->Artists
 			||	 (myLibrary->Columns() == 2 && myScreen->ActiveWindow() == myLibrary->Albums))
 			{