[sam3] add basic SMC support

include/libopencm3/sam/smc.h

@@ -0,0 +1,32 @@
+/* This provides unification of code over SAM 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(SAM3A)
+#       include <libopencm3/sam/common/smc_common_3a3u3x.h>
+#elif defined(SAM3N)
+#       error "sam3n doesn't have a static memory controller."
+#elif defined(SAM3S)
+#       include <libopencm3/sam/3s/smc.h>
+#elif defined(SAM3U)
+#       include <libopencm3/sam/common/smc_common_3a3u3x.h>
+#elif defined(SAM3X)
+#       include <libopencm3/sam/common/smc_common_3a3u3x.h>
+#else
+#       error "sam family not defined."
+#endif