minadbd: Support rescue install and getprop commands.

Bug: 128415917
Test: Enter rescue mode on taimen. Send the following commands:
      `adb rescue getprop ro.build.fingerprint`
      `adb rescue getprop ro.build.date.utc`
      `adb rescue install /path/to/package.zip`
Test: Sideload on taimen w/ `adb sideload /path/to/package.zip`.
Change-Id: Ibc25daf9fd13f7002e54789f67aaf85d06976bb8
Merged-In: Ibc25daf9fd13f7002e54789f67aaf85d06976bb8
(cherry picked from commit ed717ca1)