hw/cadence_gem: Make rx_desc_addr and tx_desc_addr uint32_t
Make the state fields rx_desc_addr and tx_desc_addr uint32_t;
this matches the VMStateDescription, and also conforms to how
hardware works: the registers don't magically become larger
if the device is attached to a CPU with a larger physical
address size. It also fixes a compile failure if the
target_phys_addr_t type is changed to 64 bits.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Peter A. G. Crosthwaite <peter.crosthwaite@petalogix.com>