Revert "block: do not notify urgent request, when flush with data in flight"

This reverts commit c286ecb5e21e76a26674b807f5ef90cc59087530.
Revert "block: allow REQ_PM requests even when the device is suspended"

This reverts commit 238b064f0330a430e754fbbd6d6d72ef33f10fd9.
Revert "block: implement runtime pm strategy"

This reverts commit af7ba93db3115b33f65c0af0e7c918cf2033074c.
Revert "block: add runtime pm helpers"

This reverts commit e8de8019062efbd11b7eca2bc01b11e22acce83e.
Revert "block: add a flag to identify PM request"

This reverts commit ebd3ce43fefd87060f2354459bb742e8c378528d.