patch 8.0.0937: user highlight groups not adjusted for terminal

Problem:    User highlight groups are not adjusted for StatusLineTerm.
Solution:   Combine attributes like for StatusLineNC.
diff --git a/src/screen.c b/src/screen.c
index fb7c3ce..05a1709 100644
--- a/src/screen.c
+++ b/src/screen.c
@@ -7257,6 +7257,11 @@
 	else if (hltab[n].userhl < 0)
 	    curattr = syn_id2attr(-hltab[n].userhl);
 #ifdef FEAT_WINDOWS
+# ifdef FEAT_TERMINAL
+	else if (wp != NULL && bt_terminal(wp->w_buffer)
+						   && wp->w_status_height != 0)
+	    curattr = highlight_stlterm[hltab[n].userhl - 1];
+# endif
 	else if (wp != NULL && wp != curwin && wp->w_status_height != 0)
 	    curattr = highlight_stlnc[hltab[n].userhl - 1];
 #endif