Misc fixes (Herve Poussineau)
- Fix internal fifo size (16 bytes), according to http://www.ibiblio.org/pub/historic-linux/early-ports/Sparc/NCR/NCR53C9X.txt
- Fix values of STAT_MI and STAT_MO
- Give a scsi ID to adapter, and prevent this ID to be used by devices
- Prevent fifo overrun in esp_mem_writeb
- Add a ESP_ERROR macro, and use it where appropriate


git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@5811 c046a42c-6fe2-441c-8c8c-71466251a162
