Correct lossless HBD/LBD mismatch segfault in daala_inv_tx

The lossless mode special-case that dispatches out to the inv 4x4 WHT
transform in Daala TX had the HDB and LBD dispatch cases backward due
to a rebase error.

Change-Id: If77b298834b1a51348fe08702a5144ea5b66df71