[ Merge of http://go/wvgerrit/147593 ] As we have decided to use hw_bcc service in Trusty to generate BCC and sign the generated certificate public key, we need to change the signature format to cose-sign1, which is defined by hw_bcc API. Bug: 221496117 Test: GtsMediaTestCase on sunfish Change-Id: I30739a0f0ae49291d343db46ad9e898663985cc8