libvpx.recipe doesn't pick the right --target for Architecture.ARM

EDIT: after reading libvpx docs I found out I misinterpreted the meaning of the --target option, but cerbero is picking the wrong one in my case anyway so there's room for an improvement

I'm building on an emulated raspbian stable environment (qemu-user-static + binfmt + nspawn) emulated host is armv7l, but target is armv6 (need to compile for raspberry pi zero)

arch armv7l

gcc -dumpmachine arm-linux-gnueabihf

but libvpx.recipe does self.configure_options += '--target=%s-%s-%s ' % (arch, platform, compiler)

resulting in --target=arm-linux-gcc

that leads to Unrecognized toolchain 'arm-linux-gcc'