x86: Support QEMU x86 targets

This commit introduces the initial U-Boot support for QEMU x86 targets.
U-Boot can boot from coreboot as a payload, or directly without coreboot.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Acked-by: Simon Glass <sjg@chromium.org>
Tested-by: Simon Glass <sjg@chromium.org>
Merged in patch 'x86: qemu: Add CMD_NET to qemu-x86_defconfig
   https://patchwork.ozlabs.org/patch/479745/
diff --git a/board/emulation/Kconfig b/board/emulation/Kconfig
new file mode 100644
index 0000000..36809fd
--- /dev/null
+++ b/board/emulation/Kconfig
@@ -0,0 +1,25 @@
+#
+# Copyright (C) 2015, Bin Meng <bmeng.cn@gmail.com>
+#
+# SPDX-License-Identifier:	GPL-2.0+
+#
+
+if VENDOR_EMULATION
+
+choice
+	prompt "Mainboard model"
+
+config TARGET_QEMU_X86
+	bool "QEMU x86"
+	help
+	  This is the QEMU emulated x86 board. U-Boot supports running
+	  as a coreboot payload as well as bare boot without coreboot.
+	  There are two types of x86 boards supported by QEMU which are
+	  supported by U-Boot. They are via QEMU '-M pc', an i440FX/PIIX
+	  chipset platform and '-M q35', a Q35/ICH9 chipset platform.
+
+endchoice
+
+source "board/emulation/qemu-x86/Kconfig"
+
+endif