FTP Download path corrected (#2636)

ftp_download() path corrected to be the same as sftp_download() function

func/backup.sh

@@ -172,6 +172,7 @@ ftp_download() {
     if [ -z "$PORT" ]; then
         PORT='21'
     fi
+    cd $BACKUP
     if [ -z $BPATH ]; then
         ftpc "get $1"
     else
@@ -490,4 +491,4 @@ b2_delete(){
     b2 authorize-account $B2_KEYID $B2_KEY > /dev/null 2>&1
 
     b2 delete-file-version $1/$2 > /dev/null 2>&1
-}
+}