[PATCH] bcm43xx: re-add bcm43xx_rng_init() call

Calls to bcm43xx_rng_init() and bcm43xx_rng_exit() got
lost due to merge trouble. Re-add them.

Signed-off-by: Michael Buesch <mb@bu3sch.de>
Signed-off-by: John W. Linville <linville@tuxdriver.com>