wifi: brcmsmac: avoid function pointer casts

An old cleanup went a little too far and causes a warning with clang-16
and higher as it breaks control flow integrity (KCFI) rules:

drivers/net/wireless/broadcom/brcm80211/brcmsmac/phy_shim.c:64:34: error: cast from 'void (*)(struct brcms_phy *)' to 'void (*)(void *)' converts to incompatible function type [-Werror,-Wcast-function-type-strict]
64 | brcms_init_timer(physhim->wl, (void (*)(void *))fn,
| ^~~~~~~~~~~~~~~~~~~~

Change this one instance back to passing a void pointer so it can be
used with the timer callback interface.

Fixes: d89a4c80601d ("staging: brcm80211: removed void * from softmac phy")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Arend van Spriel <arend.vanspriel@broadcom.com>
Signed-off-by: Kalle Valo <kvalo@kernel.org>
Link: https://msgid.link/20240213100548.457854-1-arnd@kernel.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>