571a80b261
critical mbuf fields to sane values. Simplify the use of ETHER_ALIGN to enforce payload alignment, and turn it on on the x86 as well as alpha since it helps with NFS which wants the payload to be longword aligned even though the hardware doesn't require it. This fixes a problem with the ti driver causing an unaligned access trap on the Alpha due to m_adj() sometimes not setting the alignment correctly because of incomplete mbuf initialization.