Abolish DmTargetDefaultKey::IsLegacy
To make it easier to support disk formats created using old versions
of dm-default-key with new kernels, stop checking the kernel module
version; instead, the caller decides whether to use the old or new
options format.
Bug: 150761030
Test: crosshatch and cuttlefish boot normally; cuttlefish
fails with "default-key: Not enough arguments" as expected when
option is set to 1
Cherry-Picked-From: 539b98fb58cd0efa278336139d8f4ba963dad285
Merged-In: I810bb7e085b9b8648858de1a02165162d1fd163e
Change-Id: I810bb7e085b9b8648858de1a02165162d1fd163e
3 files changed