patch 8.0.1392: build fails with --with-features=huge --disable-channel

Problem:    Build fails with --with-features=huge --disable-channel.
Solution:   Don't enable the terminal feature when the channel feature is
            missing. (Dominique Pelle, closes #2453)
diff --git a/src/configure.ac b/src/configure.ac
index d08986e..0883cb7 100644
--- a/src/configure.ac
+++ b/src/configure.ac
@@ -2059,7 +2059,7 @@
     AC_MSG_RESULT(no)
   fi
 fi
-if test "$enable_terminal" = "yes"; then
+if test "$enable_terminal" = "yes" -a "$enable_channel" = "yes"; then
   AC_DEFINE(FEAT_TERMINAL)
   TERM_SRC="libvterm/src/encoding.c libvterm/src/keyboard.c libvterm/src/mouse.c libvterm/src/parser.c libvterm/src/pen.c libvterm/src/screen.c libvterm/src/state.c libvterm/src/unicode.c libvterm/src/vterm.c"
   AC_SUBST(TERM_SRC)