[Sync] Create //components/sync/device_info.

This CL creates a new sync subfolder for all the device_info code. It is
still co-dependent on driver/, but since conceptually device_info is its
own data type it should get its own folder.

BUG=638086
TBR=jam

Review-Url: https://codereview.chromium.org/2250033002
Cr-Commit-Position: refs/heads/master@{#412301}
55 files changed