tty.cc and fhandler/tty.cc

[Takashi Yano]

Current cygwin git master has two tty.cc, one is winsup/cygwin/tty.cc
and the other is winsup/cygwin/fhandler/tty.cc (it was originally
fhandler_tty.cc). This is somewhat confusing.

fhandler/tty.cc is defining fhandler_pty_{common,master,slave} class,
so, what about renaming fhandler/tty.cc to fhandler/pty.cc?

-- 
Takashi Yano <takashi.yano@nifty.ne.jp>