Report OEMCrypto security patch level

[ Merge of http://go/wvgerrit/17959 ]

This will allow the license server to base licensing decisions on the
devices security module revision.

b/28882058

Change-Id: I574e7686bb305397946d2bfaff504cfae242e628

libwvdrmengine/cdm/core/src/crypto_session.cpp

@@ -234,6 +234,10 @@ bool CryptoSession::GetProvisioningId(std::string* provisioning_id) {
   return true;
 }
 
+uint8_t CryptoSession::GetSecurityPatchLevel() {
+  return OEMCrypto_Security_Patch_Level(requested_security_level_);
+}
+
 CdmResponseType CryptoSession::Open(SecurityLevel requested_security_level) {
   LOGV("CryptoSession::Open: Lock");
   AutoLock auto_lock(crypto_lock_);