sys_select, sys_time: port 2013-01-30 Solaris 2.6 fix to Cygwin

sys_select, sys_time: port 2013-01-30 Solaris 2.6 fix to Cygwin

Problem reported by Marco Atzeri in
<http://lists.gnu.org/archive/html/bug-gnulib/2013-03/msg00000.html>.
* lib/sys_select.in.h [HAVE_SYS_SELECT_H && _CYGWIN_SYS_TIME_H]:
Simply delegate to the system <sys/select.h> in this case too.
Also, pay attention to _GL_SYS_SELECT_H_REDIRECT_FROM_SYS_TIME_H only
if OSF/1, since otherwise Cygwin breaks, and it doesn't seem to
be needed on Solaris either.
* lib/sys_time.in.h [_CYGWIN_SYS_TIME_H]:
Simply delgate to the system <sys/time.h> in this case.