HwDisableInterruptsCallback Routine

A HwDisableInterruptsCallback routine should do the following:

1. Re-enable interrupts from the HBA.
2. Return control.

Note that this routine must execute as quickly as possible to avoid tying up I/O operations for other devices in the machine. Consequently, a HwEnableInterruptsCallback must do no more than re-enable interrupts on the HBA before it returns control.