When there is an error in init_bus() then we need to call release_bus()
before we return.

Fixes: c5c77ba1 ("staging: wilc1000: Add SDIO/SPI 802.11 driver")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>