o no more ds_vdata in tx/rx descriptors
o split h/w tx/rx descriptor from s/w status
o as part of the descriptor split change the rate control module api
so the ath_buf is passed in to the module so it can fetch both
descriptor and status information as needed
o add some const poisoning
Also for sample rate control algorithm:
o split debug msgs (node, rate, any)
o uniformly bounds check rate indices (and in some cases correct checks)
o move array index ops to after bounds checking
o use final tsi from the status block instead of the h/w descriptor
o replace h/w descriptor struct's with proper mask+shift defs (this
doesn't belong here; everything is known by the driver and should
just be sent down so there's no h/w-specific knowledge)
MFC after: 1 month
