Quant in checkpoint dtype #1968

Job	Run time
test-coreml / test-backend-linux	-1s
test-coreml / test-backend-macos (coreml, operators) / macos-job	17m 7s
test-coreml / test-backend-macos (coreml, models) / macos-job	17m 36s
test-coreml / package-golden-artifacts	0s
	34m 42s

Provide feedback