Support non-ubifs layout

Add ubifs_layout as config argument, so a build could select if it
needs ubifs_layout feature or not.

Add code to update non-ubifs layout image by
1. Putting the bmc image in /run/initramfs;
2. Set its state as Active when it is ready to update
3. Let user to initiate the reboot request

Tested: Generate a tarball with Romulus bmc image and manifest,
        update it with REST API (image upload, activation, and reboot)
        Verify the code update works well in WebUI.

Change-Id: I5b122211fafb7cb9d96ee67317db139ed0b7d0a7
Signed-off-by: Lei YU <mine260309@gmail.com>
diff --git a/static/Makefile.am.include b/static/Makefile.am.include
new file mode 100644
index 0000000..7bcfcb2
--- /dev/null
+++ b/static/Makefile.am.include
@@ -0,0 +1,2 @@
+phosphor_image_updater_SOURCES += \
+	%reldir%/flash.cpp