Build: spec: avoid long-broken (in a pristine tree state) "make all"

The main problem is a logically flawed arrangement whereby "scratch"
program (that shall be excluded in a standard compilation flow, really)
depends on something that is not readily available at the moment it
it is ordered to be compiled, leading to:

make[1]: *** No rule to make target 'lib/common/libcrmcommon.la', needed by 'scratch'. Stop.