fix: block: simplify and extend the block_bio_merge tracepoint class (v5.11)

See upstream commit:

  commit e8a676d61c07eccfcd9d6fddfe4dcb630651c29a
  Author: Christoph Hellwig <hch@lst.de>
  Date:   Thu Dec 3 17:21:36 2020 +0100

    block: simplify and extend the block_bio_merge tracepoint class

    The block_bio_merge tracepoint class can be reused for most bio-based
    tracepoints.  For that it just needs to lose the superfluous q and rq
    parameters.

Signed-off-by: Michael Jeanson <mjeanson@efficios.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: I90a1da20ab07605ed88f29b02f63134fa4aee6a8