Make GetMaxNumberOfSessions and GetNumberOfOpenSessions security level aware

Merged from Widevine CDM repo:
https://widevine-internal-review.googlesource.com/#/c/13662/

Change-Id: Id261ab16c4f987dbee78b3ecde4beebbf44f5371

libwvdrmengine/cdm/core/include/oemcrypto_adapter.h

@@ -28,6 +28,10 @@ OEMCryptoResult OEMCrypto_GetHDCPCapability(SecurityLevel level,
                                             OEMCrypto_HDCP_Capability* maximum);
 bool OEMCrypto_SupportsUsageTable(SecurityLevel level);
 bool OEMCrypto_IsAntiRollbackHwPresent(SecurityLevel level);
+OEMCryptoResult OEMCrypto_GetNumberOfOpenSessions(SecurityLevel level,
+                                                  size_t* count);
+OEMCryptoResult OEMCrypto_GetMaxNumberOfSessions(SecurityLevel level,
+                                                 size_t* maximum);
 }  // namespace wvcdm
 
 #endif  // WVCDM_CORE_OEMCRYPTO_ADAPTER_H_