x86: qemu: Support operation as an EFI payload

Disable a few things which interfere with the EFI init. This allows QEMU to
to boot into EFI, load a U-Boot payload then boot to the U-Boot prompt.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Tested-by: Bin Meng <bmeng.cn@gmail.com>
diff --git a/board/emulation/qemu-x86/Kconfig b/board/emulation/qemu-x86/Kconfig
index e777ef4..c9181fc 100644
--- a/board/emulation/qemu-x86/Kconfig
+++ b/board/emulation/qemu-x86/Kconfig
@@ -13,11 +13,12 @@
 	default "qemu-x86"
 
 config SYS_TEXT_BASE
-	default 0xfff00000
+	default 0xfff00000 if !EFI_STUB
+	default 0x01110000 if EFI_STUB
 
 config BOARD_SPECIFIC_OPTIONS # dummy
 	def_bool y
-	select X86_RESET_VECTOR
+	select X86_RESET_VECTOR if !EFI_STUB
 	select QEMU
 	select BOARD_ROMSIZE_KB_1024