x86: Rename efi-x86 target to efi-x86_app

To avoid confusion, let's rename the efi-x86 target to efi-x86_app.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
diff --git a/board/efi/efi-x86_app/Kconfig b/board/efi/efi-x86_app/Kconfig
new file mode 100644
index 0000000..ae87bf3
--- /dev/null
+++ b/board/efi/efi-x86_app/Kconfig
@@ -0,0 +1,15 @@
+if TARGET_EFI_APP
+
+config SYS_BOARD
+	default "efi-x86_app"
+
+config SYS_VENDOR
+	default "efi"
+
+config SYS_SOC
+	default "efi"
+
+config SYS_CONFIG_NAME
+	default "efi-x86_app"
+
+endif