[LTP] [PATCH] lib: tst_kconfig: Add runtime checks

[Li Wang]

> So far for CONFIG_*_NS.

It would be great to have a description for the feature:

Something maybe like:

 "Currently, LTP Kconfig parsing logic only checks if a feature was
  enabled during kernel compilation (e.g., CONFIG_USER_NS=y). However,
  some kernel features can be compiled in but disabled at runtime via
  kernel command-line parameter or sysctls. When this happens, tests
  relying on these Kconfig variables attempt to run and fail, rather
  than being gracefully skipped.
  
  This patch introduces a runtime check mechanism for Kconfig variables.
  When a monitored CONFIG_* variable is parsed as 'y' or 'm', the framework
  now executes an associated runtime check function. If the runtime check
  fails, the framework logs an info message and internally overrides the
  variable's state to 'n'. This allows the existing LTP dependency logic
  to properly skip tests that require the disabled feature."

Also, add test_kconfig04.c in newlib_tests/ to verify this works?

-- 
Regards,
Li Wang