Copy snapuserd to first_stage_ramdisk

Certain binaries, such as snapuserd, are only available under
/system/bin. To make them accessible by first stage init, we copy
/system/bin/snapuserd to /first_stage_ramdisk/system/bin/snapuserd .

Test: th
Bug: 219841787
Change-Id: I913425a82905c745a05ac32d488f08506dc264ff
2 files changed