Re-order stack startup/shutdown with btm

The btm portion is more framework than layer and may
used by the shim/gd immediately at startup.

Bug: 229906389
Tag: #refactor
Test: gd/cert/run
BYPASS_LONG_LINES_REASON: Bluetooth likes 120 lines
Ignore-AOSP-First: cherry-pick

Merged-In: Iba0ddc183aa8b45156d76d64f5473baf3e2f65fd
Change-Id: Iba0ddc183aa8b45156d76d64f5473baf3e2f65fd