[ Merge of http://go/wvgerrit/149849 ] With ECC based DRM cert, the session key is expected to be 32, as compared to 16 bytes in RSA case. This CL adds supports for 32 bytes session key. Bug: 236317198 Test: oemcrypto_test Change-Id: I657fdd92d17736a23375ddcd457f83efa6ca6d1f