Fix WINDOWSNT/DOS_NT build

Recent changes in sysdep.c and emacsclient unnecessarily
removed useful code from DOS_NT builds.  This changeset
reinstates that code.
* nt/inc/ms-w32.h (tcdrain): Redirect to _commit.
(fdatasync): No need to redirect anymore.

* lib-src/emacsclient.c (flush_stdout): Don't avoid calling
tcdrain on DOS_NT platforms.

* src/sysdep.c (reset_sys_modes): Don't ifdef away the call to
tcdrain on DOS_NT platforms.
1 job for master in 22 minutes (queued for 2 seconds)
Status Job ID Name Coverage
  Test
failed #198
test

00:22:00

 
Name Stage Failure
failed
test Test
make[2]: *** [check-doit] Error 1
Makefile:301: recipe for target 'check-doit' failed
make[2]: Leaving directory '/builds/tzz/emacs/test'
Makefile:271: recipe for target 'check' failed
make[1]: *** [check] Error 2
make[1]: Leaving directory '/builds/tzz/emacs/test'
Makefile:955: recipe for target 'check' failed
make: *** [check] Error 2
ERROR: Job failed: exit code 1