How-To: Vero 4K+ hd-idle install to spin down USB HDD's that otherwise won't

I realise that this is a thread for Vero 4K+ but I thought I would try it out on RPi4 because I have a USB disk that is not powering down and hdparam does not seem to to like it.

The “make” fails because:

go test: -race is only supported on linux/amd64, linux/ppc64le, linux/arm64, freebsd/amd64, netbsd/amd64, darwin/amd64 and windows/amd64

RPI4 with OSMC shows
uname -a
Linux media1 5.10.78-7-osmc #1 SMP PREEMPT Fri Sep 2 03:06:27 UTC 2022 aarch64 GNU/Linux

The Makefile has a section that says:
ifeq ($(PLATFORM),aarch64)
ARCH = arm64
endif

but a lower down part of the file that sets “GOARCH” does not have a similar test for aarch64

Is that a mistake in the Makefile ?