Only init legacy property environment once

Installing multiple pre-kitkat packages in succession may cause
legacy_properties_init() to fail. Only initialize the workspace once and
then just do path renames for all subsequent requests to enable legacy
props.

Change-Id: Ida528aca9322f77935411b270fdf182828abab8a
Merge branch 'cm-11.0' of github.com:CyanogenMod/android_bootable_recovery into cm-11.0