patch 8.0.0358: invalid memory access in C-indent code

Problem:    Invalid memory access in C-indent code.
Solution:   Don't go over end of empty line. (Dominique Pelle, closes #1492)
diff --git a/src/edit.c b/src/edit.c
index 25a123e..c4e7ddd 100644
--- a/src/edit.c
+++ b/src/edit.c
@@ -8181,7 +8181,8 @@
 	{
 	    if (try_match && *look == keytyped)
 		return TRUE;
-	    ++look;
+	    if (*look != NUL)
+		++look;
 	}
 
 	/*