patch 8.0.1800: X11: getting color is slow

Problem:    X11: getting color is slow.
Solution:   Avoid using sprintf() and XParseColor(), put the RGB values in
            XColor directly.
diff --git a/src/version.c b/src/version.c
index 7f7e1b6..0e1cdff 100644
--- a/src/version.c
+++ b/src/version.c
@@ -762,6 +762,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    1800,
+/**/
     1799,
 /**/
     1798,