patch 8.2.1974: Vim9: test for has('gui_running') fails with VIMDLL

Problem:    Vim9: test for has('gui_running') fails with VIMDLL.
Solution:   Adjust the #ifdef. (Ken Takata, closes #7276)

Author: brammool

src/evalfunc.c

@@ -5513,7 +5513,7 @@ dynamic_feature(char_u *feature)
 #ifdef VIMDLL
 	    || STRICMP(feature, "filterpipe") == 0
 #endif
-#if defined(FEAT_GUI) && !defined(ALWAYS_USE_GUI)
+#if defined(FEAT_GUI) && !defined(ALWAYS_USE_GUI) && !defined(VIMDLL)
 	    // this can only change on Unix where the ":gui" command could be
 	    // used.
 	    || (STRICMP(feature, "gui_running") == 0 && !gui.in_use)

src/version.c

@@ -750,6 +750,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    1974,
 /**/
     1973,
 /**/