recovery: fix sideload cancel

Change-Id: I76fcea55cc38edc713211742890b00acf8de4117
Merge "recovery: fix sideload cancel" into cm-10.1
Delete sideloaded file once installed

If not deleted, it will be unexpectedly re-installed in case
the user starts and then cancels adb sideload.

Change-Id: Idfea3b5d5c95ab29fd946cd404d1255105105ce3