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>

drivers/net/wireless/intel/ipw2x00/ipw2200.c

@@ -4093,7 +4093,7 @@ static const char *ipw_get_status_code(u16 status)
 	return "Unknown status value.";
 }
 
-static void inline average_init(struct average *avg)
+static inline void average_init(struct average *avg)
 {
 	memset(avg, 0, sizeof(*avg));
 }