Disable kallsyms

Change-Id: Icc0e5e81f16bf317891d296e92e63dff53d44481
Further Makefile tuning

Change-Id: I16ee4ef11233db7c152d2815fe8ae394ffe72f08
Remove ext2&ext3 and make ext4 used for those

Change-Id: I0442c5e6e4ce46ea59c443e994a5f79b354a2f36