Revert "block: make register_disk() static"

This reverts commit 5504278ce812f89a7dbf33e59e84a31265f583b0.
Revert "block: fix blk_queue_end_tag()"

This reverts commit 077f1acc6e48578f2dd95572ed18d8e9d0a0d206.
Revert "block: re-use existing 'reading' variable instead of checking direction again"

This reverts commit ca2566a266e3843bb063925352ab51ed0c0ac3cb.
Revert Añadidos patch CONFIG_BCMDHD (se eliminaron en update11)