When performing our register test, be careful

When performing our register test, be careful
to avoid resetting the chip when pausing the
controller.  The test reads the HCNTRL register
and then writes it back with the PAUSE bit
explicitly set.  If the last write to the controller
before our probe is to reset it, the CHIPRST
bit will still be set, so we must mask it off
before the PAUSE operation.  On some chip versions,
we cannot access registers for a few 100us after
a reset, so this inadvertant reset was causing PCI
errors to occur on the read to check for paused
status.

Obtained-from: FreeBSD