sfc: Increase MCDI status timeout to 250ms

The SFC9120 MC firmware often takes longer than 20ms to reboot and
update the warm boot count in BIU_MC_SFT_STATUS_REG.  A timeout of
250ms is very generous for an MC reboot.

Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
1 file changed