Globally serialize XNNPACK execution, add logging (#19742) #6068

Job	Run time
test-xnnpack / test-backend-linux (xnnpack, models) / linux-job	24m 21s
test-xnnpack / test-backend-linux (xnnpack_static_int8_per_channel, operators) / linux-job	30m 50s
test-xnnpack / test-backend-linux (xnnpack_static_int8_per_tensor, models) / linux-job	22m 16s
test-xnnpack / test-backend-linux (xnnpack, operators) / linux-job	15m 9s
test-xnnpack / test-backend-linux (xnnpack_dynamic_int8_per_channel, operators) / linux-job	19m 9s
test-xnnpack / test-backend-linux (xnnpack_dynamic_int8_per_channel, models) / linux-job	18m 12s
test-xnnpack / test-backend-linux (xnnpack_static_int8_per_channel, models) / linux-job	23m 11s
test-xnnpack / test-backend-linux (xnnpack_static_int8_per_tensor, operators) / linux-job	26m 19s
test-xnnpack / test-backend-macos	0s
test-xnnpack / package-golden-artifacts	5m 30s
	3h 4m 57s

Provide feedback