block-backend: align max_transfer to request alignment

Block device requests must be aligned to bs->bl.request_alignment.
It makes sense for drivers to align bs->bl.max_transfer the same
way; however when there is no specified limit, blk_get_max_transfer
just returns INT_MAX.  Since the contract of the function does not
specify that INT_MAX means "no maximum", just align the outcome
of the function (whether INT_MAX or bs->bl.max_transfer) before
returning it.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
1 file changed