iwlwifi: move iwl_set_rxon_hwcrypto and mark it static

iwl_set_rxon_hwcrypto is used only in
iwl-agn-rxon.c. Move it there and mark it
static.

Signed-off-by: Meenakshi Venkataraman <meenakshi.venkataraman@intel.com>
Signed-off-by: Wey-Yi Guy <wey-yi.w.guy@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

diff --cc drivers/net/wireless/iwlwifi/iwl-agn-rxon.c
Simple merge

diff --cc drivers/net/wireless/iwlwifi/iwl-core.c
Simple merge

diff --cc drivers/net/wireless/iwlwifi/iwl-core.h
Simple merge