patch 8.1.1297: invalid argument test fails without GTK

Problem:    Invalid argument test fails without GTK.
Solution:   Test -display and --display separately.
diff --git a/src/testdir/test_startup.vim b/src/testdir/test_startup.vim
index a45130f..61c5082 100644
--- a/src/testdir/test_startup.vim
+++ b/src/testdir/test_startup.vim
@@ -422,7 +422,7 @@
     endfor
   endif
 
-  if has('clipboard')
+  if has('gui_gtk')
     let out = split(system(GetVimCommand() .. ' --display'), "\n")
     call assert_equal(1, v:shell_error)
     call assert_match('^VIM - Vi IMproved .* (.*)$',         out[0])
@@ -430,6 +430,14 @@
     call assert_equal('More info with: "vim -h"',            out[2])
   endif
 
+  if has('clipboard')
+    let out = split(system(GetVimCommand() .. ' -display'), "\n")
+    call assert_equal(1, v:shell_error)
+    call assert_match('^VIM - Vi IMproved .* (.*)$',         out[0])
+    call assert_equal('Argument missing after: "-display"', out[1])
+    call assert_equal('More info with: "vim -h"',            out[2])
+  endif
+
   let out = split(system(GetVimCommand() .. ' -ix'), "\n")
   call assert_equal(1, v:shell_error)
   call assert_match('^VIM - Vi IMproved .* (.*)$',          out[0])
diff --git a/src/version.c b/src/version.c
index 8e6b404..da0d1df 100644
--- a/src/version.c
+++ b/src/version.c
@@ -768,6 +768,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    1297,
+/**/
     1296,
 /**/
     1295,