rpm: Introduce LIBGUESTFSTOOLS_VERSION
rpm: Introduce LIBGUESTFSTOOLS_VERSION

The tools are developed and released separately from the library
these days, so we need to be able to pin different version
numbers.

Signed-off-by: Andrea Bolognani <3ada0bee826c753786fdbba72243dfba997094cf@redhat.com>

kubevirt/kubevirt,kubevirt/kubevirt,kubevirt/kubevirt,kubevirt/kubevirt