iwlwifi: dvm: don't enable CTS to self

iwlwifi: dvm: don't enable CTS to self

commit 43d826ca5979927131685cc2092c7ce862cb91cd upstream.

We should always prefer to use full RTS protection. Using
CTS to self gives a meaningless improvement, but this flow
is much harder for the firmware which is likely to have
issues with it.

Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
[bwh: Backported to 3.2:
 - Adjust filename
 - Condition for RXON_FLG_SELF_CTS_EN in iwlagn_commit_rxon() was different]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>