Convert sata_sil to new EH. As these controllers have hardware
interrupt mask and are known to have screaming interrupts issues, use
hardware IRQ masking for freezing. sil_freeze() masks interrupts for
the port and sil_thaw() unmasks them. As ports are automatically
frozen before probing reset, there is no need to initialize interrupt
masks sil_init_onde(). Remove related code.
Other than freezing, sata_sil uses stock BMDMA EH routines.