HVCC

add recommended ScopedIrqBlocker to deal with interupt race condition… #56

Job	Run time
test (3.8)	2m 9s
build	1m 3s
test (3.9)	2m 6s
test (3.10)	2m 8s
test (3.11)	2m 9s
test (3.12)	2m 12s
dispatch (Wasted-Audio/hvcc-examples-dpf)	4s
dispatch (Wasted-Audio/hvcc-examples-js)	3s
	11m 54s

Provide feedback