wifi: brcmfmac: add linefeed at end of file

The following sparse warning was reported:

drivers/net/wireless/broadcom/brcm80211/brcmfmac/fwil.c:432:49:
warning: no newline at end of file

Fixes: 31343230abb1 ("wifi: brcmfmac: export firmware interface functions")
Reported-by: Jakub Kicinski <[e-mail]>
Closes: https://lore.kernel.org/all/[e-mail]/
Signed-off-by: Arend van Spriel <[e-mail]>
Signed-off-by: Kalle Valo <[e-mail]>
Link: https://msgid.link/[e-mail]