Warn for incompatible uses of 'option env=...'
Warn for incompatible uses of 'option env=...'

Since commit cbf32e2 ("Expand environment variables in strings
directly"), Kconfiglib expands environment variables directly in strings
instead of using the 'option env=...' mechanism (this is planned for the
C tools too). This new behavior is backwards-compatible as long as all
'option env=...' symbols have the same name as the environment variables
they reference.

Warn if 'option env="FOO"' appears on a symbol that isn't named FOO, to
point out compatibility issues and help with debugging.

ulfalizer/Kconfiglib,ulfalizer/Kconfiglib