Create a mirror directory for misc_ce and misc_de storage by bind
mounting the respective directories. This is done for the defaul null
volume only, and other volumes are handled at a later staged.
When an SDK sandbox process is spawned and data isolation needs to
occur, the sdksandbox directories present in the misc directories will
be used to bind mount from, after tmpfs is mounted on the original.
Bug: 214241165
Test: atest SdkSandboxStorageHostTest
Ignore-AOSP-First: Will cherry pick based on other CLs in the topic
Change-Id: Icb1dc7d7fbd53a5c3853acf2f9d4d75b278d7295