xfs: pass the xfs_bmbt_irec directly through the log intent code

[ Upstream commit ddccb81b ]

Instead of repeatedly boxing and unboxing the incore extent mapping
structure as it passes through the BUI code, pass the pointer directly
through.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Leah Rumancik <leah.rumancik@gmail.com>
Acked-by: "Darrick J. Wong" <djwong@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>