Fix typo in README

Thanks @Raulkumar for finding this in #1118

README.rst

@@ -64,7 +64,7 @@ The Windows version of TigerVNC contains the following programs:
 * winvnc - the TigerVNC Server for Windows.  winvnc allows a Windows desktop to
            be accessed remotely using a VNC viewer.
 
-WARNING: winvnc is currently unmaintainted and and may not function correctly.
+WARNING: winvnc is currently unmaintained and and may not function correctly.
 
 winvnc may not work if the Fast User Switching or Remote Desktop features are
 in use.