Revert to old-style API for EC_KEY handling

Nothing using the EVP_PKEY correctly, so we should revert to the EC_KEY
and ECDSA interfaces. Unfortunately, the SSL client certificate library
uses EC_KEY directly, so just having the EVP_PKEY interface doesn't
work.

Remove the EVP_PKEY interface entirely because it just adds complexity
since the EC_KEY path will do the same thing.

Bug: 10655329
Change-Id: I97d17068297c33477b3b9f754f2713fdf258d646
diff --git a/keystore-engine/methods.h b/keystore-engine/methods.h
index 8535ac9..fb85942 100644
--- a/keystore-engine/methods.h
+++ b/keystore-engine/methods.h
@@ -61,6 +61,10 @@
 void ex_data_free(void *);
 void ex_data_clear_free(void *);
 
+/* ECDSA */
+int ecdsa_register(ENGINE *);
+int ecdsa_pkey_setup(ENGINE *, EVP_PKEY*, const char*);
+
 /* DSA */
 int dsa_register(ENGINE *);
 int dsa_pkey_setup(ENGINE *, EVP_PKEY*, const char*);