docs: kbuild: fix typo

Work on kconfig is welcomed on both areas of clarifying semantics and on

evaluating the use of a full SAT solver for it. A full SAT solver can be

desirable to enable more complex dependency mappings and / or queries,

for instance on possible use case for a SAT solver could be that of handling

for instance one possible use case for a SAT solver could be that of handling

the current known recursive dependency issues. It is not known if this would

address such issues but such evaluation is desirable. If support for a full SAT

solver proves too complex or that it cannot address recursive dependency issues