Revert "Bfq patch3"

This reverts commit 196a1b344834c7d839ec3f1a039d49b70e015402.
Revert "Bfq patch2"

This reverts commit 40518b1596d6b9fb43817c85d46f2b582b872cfd.
Revert "Bfq patch1"

This reverts commit 80769f70cacf3871d080deef4e54b7a18c36c543.
Cfq io scheduler as the default