idpf: remove obsolete stashing code

jira KERNEL-168
commit-author Joshua Hay <joshua.a.hay@intel.com>
commit 6c4e684
upstream-diff |
	- adjusted context in .h due to different order in the struct idpf_tx_queue
	- adjusted context due to missing idpf_tx_read_tstamp func;
	both are due to missing
	1a49cf8 ("idpf: add Tx timestamp flows").
	- did not include libeth_cacheline_set_assert for struct idpf_tx_queue
	due to missing 5a816aa
	("idpf: strictly assert cachelines of queue and queue vector structures")

With the new Tx buffer management scheme, there is no need for all of
the stashing mechanisms, the hash table, the reserve buffer stack, etc.
Remove all of that.

	Signed-off-by: Joshua Hay <joshua.a.hay@intel.com>
	Reviewed-by: Madhu Chittim <madhu.chittim@intel.com>
	Reviewed-by: Aleksandr Loktionov <aleksandr.loktionov@intel.com>
	Tested-by: Samuel Salin <Samuel.salin@intel.com>
	Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
(cherry picked from commit 6c4e684)
	Signed-off-by: Roxana Nicolescu <rnicolescu@ciq.com>

Author: jahay1