build: rename non-generated linker scripts to .ld extension

Avoids confusion with .gitignore rules, which were inadequate to
cover all the places where these files are found. At least in
VIM, these files are now syntax highlighted correctly.

Change-Id: I23810b0ed34129320cc2760e19ed1a610afe039e
Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>

arch/x86/soc/ia32/linker.ld

@@ -0,0 +1,59 @@
+/*
+ * Copyright (c) 2011-2014, Wind River Systems, Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/**
+ * @file
+ * @brief Linker command/script file
+ *
+ * This is the linker script for both standard images and XIP images.
+ */
+
+#include <autoconf.h>
+
+/* physical address where the kernel is loaded */
+#define PHYS_LOAD_ADDR CONFIG_PHYS_LOAD_ADDR
+
+/* physical address of RAM */
+#ifdef CONFIG_XIP
+  #define PHYS_RAM_ADDR    CONFIG_PHYS_RAM_ADDR
+#else  /* !CONFIG_XIP */
+  #define PHYS_RAM_ADDR    PHYS_LOAD_ADDR
+#endif /* CONFIG_XIP */
+
+MEMORY
+    {
+#ifdef CONFIG_XIP
+    ROM (rx)        : ORIGIN = PHYS_LOAD_ADDR, LENGTH = CONFIG_ROM_SIZE*1K
+    RAM (wx)        : ORIGIN = PHYS_RAM_ADDR, LENGTH = CONFIG_RAM_SIZE*1K
+#else  /* !CONFIG_XIP */
+    RAM (wx)	    : ORIGIN = PHYS_LOAD_ADDR, LENGTH = CONFIG_RAM_SIZE*1K
+#endif /* CONFIG_XIP */
+
+    /*
+     * It doesn't matter where this region goes as it is stripped from the
+     * final ELF image. The address doesn't even have to be valid on the
+     * target. However, it shouldn't overlap any other regions.
+     */
+
+    IDT_LIST        : ORIGIN = 2K, LENGTH = 2K
+    }
+
+#include <arch/x86/linker-common-sections.h>
+
+/* start adding platform specific linker sections here */
+
+/* no sections should appear after linker-epilog.h */
+#include <arch/x86/linker-epilog.h>