patch 8.1.2081: the spell.c file is too big

Problem:    The spell.c file is too big.
Solution:   Move the code for spell suggestions to a separate file. (Yegappan
            Lakshmanan, closes #4988)
diff --git a/src/version.c b/src/version.c
index 44d4d04..fa78a08 100644
--- a/src/version.c
+++ b/src/version.c
@@ -758,6 +758,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    2081,
+/**/
     2080,
 /**/
     2079,