patch 8.0.1010: build failure without termresponse feature

Problem:    Build failure without termresponse feature.
Solution:   Add #ifdef.
diff --git a/src/term.c b/src/term.c
index fec50d5..fdae4ea 100644
--- a/src/term.c
+++ b/src/term.c
@@ -3780,8 +3780,12 @@
     int
 blink_state_is_inverted()
 {
+#ifdef FEAT_TERMRESPONSE
     return rbm_status == STATUS_GOT && rcs_status == STATUS_GOT
 		&& initial_cursor_blink != initial_cursor_shape_blink;
+#else
+    return FALSE;
+#endif
 }
 
 /*