x86: Move install_e820_map() out of zimage.c

install_e820_map() has nothing to do with zimage related codes.
Move it to a dedicated place.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Acked-by: Simon Glass <sjg@chromium.org>
diff --git a/arch/x86/lib/e820.c b/arch/x86/lib/e820.c
new file mode 100644
index 0000000..5babfde
--- /dev/null
+++ b/arch/x86/lib/e820.c
@@ -0,0 +1,37 @@
+/*
+ * Copyright (C) 2015, Bin Meng <bmeng.cn@gmail.com>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <common.h>
+#include <asm/e820.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+/*
+ * Install a default e820 table with 4 entries as follows:
+ *
+ *	0x000000-0x0a0000	Useable RAM
+ *	0x0a0000-0x100000	Reserved for ISA
+ *	0x100000-gd->ram_size	Useable RAM
+ *	CONFIG_PCIE_ECAM_BASE	PCIe ECAM
+ */
+__weak unsigned install_e820_map(unsigned max_entries,
+				 struct e820entry *entries)
+{
+	entries[0].addr = 0;
+	entries[0].size = ISA_START_ADDRESS;
+	entries[0].type = E820_RAM;
+	entries[1].addr = ISA_START_ADDRESS;
+	entries[1].size = ISA_END_ADDRESS - ISA_START_ADDRESS;
+	entries[1].type = E820_RESERVED;
+	entries[2].addr = ISA_END_ADDRESS;
+	entries[2].size = gd->ram_size - ISA_END_ADDRESS;
+	entries[2].type = E820_RAM;
+	entries[3].addr = CONFIG_PCIE_ECAM_BASE;
+	entries[3].size = CONFIG_PCIE_ECAM_SIZE;
+	entries[3].type = E820_RESERVED;
+
+	return 4;
+}