兼容 asr1903

Change-Id: I3888f1adc86ea1fa73af4996d31f40223c0e5735
diff --git a/mbtk/libmbtk_lib/ftp/mbtk_ftp_at.c b/mbtk/libmbtk_lib/ftp/mbtk_ftp_at.c
index 958b0d0..fd10045 100755
--- a/mbtk/libmbtk_lib/ftp/mbtk_ftp_at.c
+++ b/mbtk/libmbtk_lib/ftp/mbtk_ftp_at.c
@@ -240,7 +240,7 @@
 int mbtk_at_ftp_upload(char *remote_path,char *local_path, int size_byte, int rest_size)
 {
     int at_ftp_ret=-1;
-    int len_size;
+    int len_size = 0;
     char send_buf[1024];
 
     mbtk_at_ftp_par_at.at_ftp_handle = mbtk_ftp_init(mbtk_at_ftp_par_at.host, mbtk_at_ftp_par_at.port, mbtk_at_ftp_par_at.auth_type,