bcm-vk: add bcm_vk UAPI

Add user space api for bcm-vk driver.

Provide ioctl api to load images and issue reset command to card.
FW status registers in PCI BAR space also defined as part
of API so that user space is able to interpret these memory locations
as needed via direct PCIe access.

Acked-by: Olof Johansson <olof@lixom.net>
Signed-off-by: Scott Branden <scott.branden@broadcom.com>
Link: https://lore.kernel.org/r/20210120175827.14820-2-scott.branden@broadcom.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>