brcmsmac: make brcms_c_stf_ss_update() void

Fix the following coccicheck warning:

drivers/net/wireless/broadcom/brcm80211/brcmsmac/stf.c:309:5-13:
Unneeded variable: "ret_code". Return "0" on line 328

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Jason Yan <yanaijie@huawei.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20200413082126.22572-1-yanaijie@huawei.com

brcmsmac: Initialize power in brcms_c_stf_ss_algo_channel_get()

wlc_phy_txpower_get_current() does a logical OR of power->flags, which
presumes that power.flags was initiliazed earlier by the caller,
unfortunately, this is not the case, so make sure we zero out the struct
tx_power before calling into wlc_phy_txpower_get_current().

Reported-by: coverity (CID 146011)
Fixes: 5b435de0d7868 ("net: wireless: add brcm80211 drivers")
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Acked-by: Arend van Spriel <arend.vanspriel@broadcom.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>

brcm80211: move under broadcom vendor directory

Part of reorganising wireless drivers directory and Kconfig. Note that I had to
edit Makefiles from subdirectories to use the new location.

Signed-off-by: Kalle Valo <kvalo@codeaurora.org>