iwlagn: don't always split remain-on-channel

iwlagn: don't always split remain-on-channel

Due to the P2P context always having the associated
bit set when we got to this code, we were splitting
up the remain-on-channel durations unconditionally.
This isn't needed -- if the P2P context is in P2P
device type mode it doesn't impose restrictions on
timing to skip it in that case.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Wey-Yi Guy <wey-yi.w.guy@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>