Merge branch 'net-ipa-kill-endpoint-stop-workaround'

Alex Elder says:

====================
net: ipa: kill endpoint stop workaround

It turns out that a workaround that performs a small DMA operation
between retried attempts to stop a GSI channel is not needed for any
supported hardware.  The hardware quirk that required the extra DMA
operation was fixed after IPA v3.1.  So this series gets rid of that
workaround code, along with some other code that was only present to
support it.

NOTE:  This series depends on (and includes/duplicates) another patch
       that has already been committed in the net tree:
         713b6ebb4c37 net: ipa: fix a bug in ipa_endpoint_stop()
====================

Signed-off-by: David S. Miller <davem@davemloft.net>