patch 9.1.1266: MS-Windows: type conversion warnings

Problem:  MS-Windows: type conversion warnings
Solution: cast the variables (Yegappan Lakshmanan)

closes: #17027

Signed-off-by: Yegappan Lakshmanan <yegappan@yahoo.com>
Signed-off-by: Christian Brabandt <cb@256bit.org>
diff --git a/src/findfile.c b/src/findfile.c
index 2bd1e7e..fd2d69f 100644
--- a/src/findfile.c
+++ b/src/findfile.c
@@ -1166,7 +1166,8 @@
 			    if (*suf == NUL)
 				break;
 			    file_path.length = len + copy_option_part(&suf,
-				  file_path.string + len, MAXPATHL - len, ",");
+				  file_path.string + len,
+				  (int)(MAXPATHL - len), ",");
 			}
 		    }
 		}