Add preliminary support for Cryptographic coprocessor on stm32 F2 and F4

include/libopencm3/stm32/crypto.h

@@ -0,0 +1,27 @@
+/* This provides unification of code over STM32F subfamilies */
+
+/*
+ * This file is part of the libopencm3 project.
+ *
+ * This library is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this library.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#if defined(STM32F2)
+#       include <libopencm3/stm32/f2/crypto.h>
+#elif defined(STM32F4)
+#       include <libopencm3/stm32/f4/crypto.h>
+#else
+#       error "CRYPTO processor is supported only" \
+	"in stm32f2xx, stm32f41xx, stm32f42xx and stm32f43xx family."
+#endif