Refactor: Separate asymmetric key types.

Change-Id: I3368798a8ecea319bb0bfcd6ff24e9a7b6287c80
diff --git a/openssl_utils.h b/openssl_utils.h
index 7ea015f..65b2447 100644
--- a/openssl_utils.h
+++ b/openssl_utils.h
@@ -20,6 +20,10 @@
 #include <openssl/evp.h>
 #include <openssl/bn.h>
 
+#include <UniquePtr.h>
+
+#include <keymaster/keymaster_defs.h>
+
 struct EVP_PKEY_Delete {
     void operator()(EVP_PKEY* p) const { EVP_PKEY_free(p); }
 };