patch 9.0.0126: expanding file names fails in dir with more than 255 entries

Problem:    Expanding file names fails in directory with more than 255
            entries.
Solution:   Use an int instead of char_u to count. (John Drouhard,
            closes #10818)
diff --git a/src/findfile.c b/src/findfile.c
index 12e76b4..881eef1 100644
--- a/src/findfile.c
+++ b/src/findfile.c
@@ -75,7 +75,7 @@
     // of wc_part
     char_u		**ffs_filearray;
     int			ffs_filearray_size;
-    char_u		ffs_filearray_cur;   // needed for partly handled dirs
+    int			ffs_filearray_cur;   // needed for partly handled dirs
 
     // to store status of partly handled directories
     // 0: we work on this directory for the first time