riscv: ISA-1.9.1 and GCC-6.3.0 adaptions

Adds 1.9.1 support to base-hw

Note:
* the kernel timer is not working
* dynamic linking is currently not supported

repos/base/include/drivers/defs/riscv.h

@@ -0,0 +1,25 @@
+/*
+ * \brief  MMIO and IRQ definitions for RISC-V (1.9.1)
+ * \author Sebastian Sumpf
+ * \date   2017-05-29
+ */
+
+/*
+ * Copyright (C) 2013-2017 Genode Labs GmbH
+ *
+ * This file is part of the Genode OS framework, which is distributed
+ * under the terms of the GNU Affero General Public License version 3.
+ */
+
+#ifndef _INCLUDE__DRIVERS__DEFS__RISCV_H_
+#define _INCLUDE__DRIVERS__DEFS__RISCV_H_
+
+namespace Riscv {
+	enum {
+		RAM_0_BASE = 0x81000000,
+		RAM_0_SIZE = 0x6e00000,
+	};
+}
+
+#endif /* _INCLUDE__DRIVERS__DEFS__RISCV_H_ */
+