Port to Solaris 10

Port to Solaris 10

* configure.ac: Instead of AC_CHECK_HEADER, use AC_COMPILE_IFELSE
with X11/Intrinsic.h when checking for X11/extensions/Xrender.h.
This suppresses a bogus "report a bug to bug-gnu-emacs" diagnostic
from 'configure' in Solaris 10.
(SETUP_SLAVE_PTY): Adjust to recent renaming of forkin to
std_in in callproc.c.  Needed on Solaris and Unixware.
* lib-src/Makefile.in (LIB_GETRANDOM, LIBS_ETAGS): New vars,
needed because on Solaris 10 the Gnulib tempname module now needs
the -lrt library for clock_gettime.  Throw in the LIB_GETRANDOM
stuff too while we’re at it; from getrandom.m4 it seems to be
needed for MingW.
(LIBS_MOVE, etags_libs): Use them.
* src/callproc.c [SETUP_SLAVE_PTY]: Include sys/stream.h
and sys/stropts.h, for SETUP_SLAVE_PTY’s definiens.
* src/process.c [NEED_BSDTTY]: Don’t include bsdtty.h; hasn’t been
needed in years.
[USG5_4]: Don’t include sys/stream.h or sys/stropts.h; these
directives havbe been moved to callproc.c because the only use of
SETUP_SLAVE_PTY is there now.