Move canned_fs_config into libcutils

It's no longer specific to make_ext4fs, will be used for mksquashfs as
well.

BUG: 27467028
Change-Id: I41b8c2b168ada45c8378dee522391edfb8f6b9a6
Signed-off-by: Mohamad Ayyash <mkayyash@google.com>
BUG: 28704419
3 files changed