kconfiglib: Expose parsing location to Python preprocessor functions

Update Kconfiglib (and menuconfig/guiconfig, just to sync) to upstream
revision f2ce282eca, to get this commit in:

    Allow preprocessor user functions to access the parsing location

    Just requires making Kconfig.filename/linenr public.

    'lineno' would be a more standard name, but be consistent with
    MenuNode.linenr.

This can be used to give friendly errors in
scripts/kconfig/kconfigfunctions.py, e.g. for
https://github.com/zephyrproject-rtos/zephyr/pull/18752

.

Some minor optimizations are included too.

Signed-off-by: Ulf Magnusson <Ulf.Magnusson@nordicsemi.no>