nios2: move soc to top-level dir soc/

Move the SoC outside of the architecture tree and put them at the same
level as boards and architectures allowing both SoCs and boards to be
maintained outside the tree.

Signed-off-by: Anas Nashif <anas.nashif@intel.com>

soc/nios2/nios2f-zephyr/linker.ld

@@ -0,0 +1,13 @@
+/*
+ * Copyright (c) 2016 Intel Corporation
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+/**
+ * @brief Linker script for the Nios II/e CPU with timer and 16550 UART
+ */
+
+#include <layout.h>
+#include <generated_dts_board.h>
+#include <arch/nios2/linker.ld>