kconfig/merge_config.sh: Accept a single file
kconfig/merge_config.sh: Accept a single file

merge_config.sh can usefully be applied to a single file.
It implicitly merges with the default configuration.

Signed-off-by: Gabriel de Perthuis <843a75370426f43c9f55429eba28765b7d21ad89@gmail.com>
Signed-off-by: Michal Marek <0c835876a532a476f30fdb1f6e963bae6c5a1a04@suse.com>

KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs