Fix message ring send path:
- define msgrng_access_enable() which disables local interrupts
and enables message ring access. Also define msgrng_restore() which
restores interrupts
- remove all other msgrng enable/disable macros, no need of critical_enter
and other locking here.
- message_send() fixup: re-read status until pending bit clears
- message_send_retry() fixup: retry only few times with interrupts disabled
- Fix up message_send/message_send_retry callers - call
msgrng_access_enable() and msgrng_restore() correctly so that interrupts
are not disabled for long.
- removed unused and obsolete code from sys/mips/rmi/msgring.h
- some style fixes - more later
rge.c (XLR GMAC driver):
- updated for the message ring changes
- remove unused message_send_block()
- retry on credit failure, this is not a permanent failure when credits
are configured correctly. Add panic if credits are not available to
send for a long time.
- style(9) fixes to mips/rmi platform files
- update pic.h to add pic_setup_intr() and use pic_setup_intr() for setting
up interrupts which are routed thru PIC.
- remove rmi_spin_mutex_safe and haslock, and make sure that the functions
are called only after mutexes are available.
