patch 8.1.1472: add_termcap_entry() is not tested

Problem:    Add_termcap_entry() is not tested.
Solution:   Add a simple test.

src/testdir/test_termcodes.vim

@@ -626,7 +626,6 @@ func Test_xterm_mouse_click_in_fold_columns()
 endfunc
 
 " This only checks if the sequence is recognized.
-" TODO: check that the values were parsed properly
 func Test_term_rgb_response()
   set t_RF=x
   set t_RB=y
@@ -712,3 +711,10 @@ func Test_xx_term_style_response()
 
   set t_RV=
 endfunc
+
+func Test_get_termcode()
+  let k1 = &t_k1
+  set t_k1=
+  set t_k1&
+  call assert_equal(k1, &t_k1)
+endfunc

src/version.c

@@ -767,6 +767,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    1472,
 /**/
     1471,
 /**/