Revert "sched: hh"

This reverts commit 65a84995272baa07c55ac8e5ccc66cf36144c5ab.
Revert "block: Reserve only one queue tag for sync IO if only 3 tags are available"

This reverts commit 9d4e85f4630cb6be447b7cd5cb23c6f181215da2.
Revert "Add SIO and FIOPS i/o schedulers"

This reverts commit 409706f06f0217ab92abb6cef81e0e48638bb2be.
block: hh