My understanding is that SENSORS_API_VERSION should be the same
as $(LIBMAINVER)$(LIBMINORVER) in lib/Module.mk. This means that
the first digit of SENSORS_API_VERSION needs to be incremented whenever
API *or* ABI changes, because we have to increment LIBMAINVER even if
only ABI changes to avoid program breakage.
Signed-off-by: Ondřej Lysoněk <olysonek@redhat.com>