iwlwifi: fix exit from stay_in_table state

When exiting from stay in table state (e.g. timer expiration),
all the statistics are reset and the RS flow should not continue
but only after enough statistics are collected again.

Signed-off-by: Guy Cohen <guy.cohen@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>