wireless: ipw2200: fix old-style declaration

Modern C standards expect the 'inline' keyword to come before the return
type in a declaration, and we get a warning for this with "make W=1":

drivers/net/wireless/intel/ipw2x00/ipw2200.c:4096:1: error: 'inline' is not at beginning of declaration [-Werror=old-style-declaration]

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Stanislav Yakovlev <stas.yakovlev@gmail.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>