Revert "[HACK] Temporarily disable block format"

This reverts commit 64b6d9aee14e8a80938157d8b6ccf2083945a739.
Use block and flag it.

Change-Id: Ic2ac31b89ea0fb691de2262a2c266d561b6de7c8
Signed-off-by: cj360 <ayunker551@gmail.com>

Conflicts:
	core/Makefile
	tools/releasetools/edify_generator.py