jme: Always save TX interrupt CPUID

This will be used to unify the ifnet.if_cpuid and ifnet.if_npoll_cpuid
igb: Save TX interrupt CPUID into tx_ring struct

This will be used to unify the ifnet.if_cpuid and ifnet.if_npoll_cpuid
kernel/dm: Remove some unused variables.

Also start using a previously unused variable in dm_target_crypt.
kernel/disk: Remove some unused variables and add __debugvar.
kernel: Remove some unused variables in kern/, opencrypto/ and platform/.
kernel/netinet6: Remove some unused variables.
if: Move if_cpuid into ifaltq; prepare multiple TX queues support

if_cpuid and if_npoll_cpuid are merged and moved into ifaltq as
altq_cpuid, which indicates the owner CPU of the tx queue.  Since
we already have code in if_start_dispatch() to catching tx queue
owner CPU changes, this merging is quite safe.
pktgen: Allow pktgenctl to specify # of packets to be queued onto TX queue
if: Move if_start_nmsg into ifaltq; prepare multiple TX queue support

While im here, also rename some functions to be consistent in naming
convention.
Merge branch 'master' into gsocdrm_jfree