brcmsmac: Use kstrdup to simplify code
Replace a kmalloc+strcpy by an equivalent kstrdup in order to improve
readability.
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Acked-by: Arend van Spriel <arend@broadcom.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>