patch 8.0.1543: with 'termguicolors' Normal color doesn't work correctly

Problem:    With 'termguicolors' Normal color doesn't work correctly.
Solution:   Set cterm_normal_bg_gui_color and cterm_normal_fg_color always.
            (Kazunobu Kuriyama, closes #981, closes #2332)
diff --git a/src/version.c b/src/version.c
index 462f746..09dcc57 100644
--- a/src/version.c
+++ b/src/version.c
@@ -779,6 +779,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    1543,
+/**/
     1542,
 /**/
     1541,