Use accessor for EVP_PKEY types am: 39b1ba3702 am: c4f9d05b28 am: f8bdea52f4 am: 2d487df20f

Original change: https://android-review.googlesource.com/c/platform/system/keymaster/+/2148656

Change-Id: I630cfc976b09310ddbc18af34651c9a633eeda31
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>