USB: bcma: add bcm53xx support

The Broadcom ARM SoCs with this usb core need a different
initialization and they have a different core id. This patch adds
support for these USB 2.0 core.

Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>