Add functions to set ECDSA_METHOD structure.

Add various functions to allocate and set the fields of an ECDSA_METHOD
structure.

crypto/ecdsa/ecs_err.c

@@ -73,6 +73,7 @@ static ERR_STRING_DATA ECDSA_str_functs[]=
 {ERR_FUNC(ECDSA_F_ECDSA_DATA_NEW_METHOD),	"ECDSA_DATA_NEW_METHOD"},
 {ERR_FUNC(ECDSA_F_ECDSA_DO_SIGN),	"ECDSA_do_sign"},
 {ERR_FUNC(ECDSA_F_ECDSA_DO_VERIFY),	"ECDSA_do_verify"},
+{ERR_FUNC(ECDSA_F_ECDSA_METHOD_NEW),	"ECDSA_METHOD_new"},
 {ERR_FUNC(ECDSA_F_ECDSA_SIGN_SETUP),	"ECDSA_sign_setup"},
 {0,NULL}
 	};