6.58.9.1: update_package: fix cm updater

* this is due to the discrepency that philz symlinks /data/media/0/
  to /sdcard/ while android, cwm, and twrp symlink from /data/media/
* the update script that cmupdater uses hard-codes /sdcard/0/
* let's just replace /sdcard/0/ with /sdcard/ when we see it

Change-Id: I4c57f706b211d99e35fce4e8deee8617dcd63c27