hw/net/cadence_gem: use FIELD to describe [TX|RX]STATUS register fields Use de FIELD macro to describe the TXSTATUS and RXSTATUS register fields. Signed-off-by: Luc Michel <luc.michel@amd.com> Reviewed-by: sai.pavan.boddu@amd.com Message-id: 20231017194422.4124691-7-luc.michel@amd.com Signed-off-by: Peter Maydell <peter.maydell@linaro.org>