This commit updates all deprecated `CONFIG_LIB_CPLUSPLUS` usages to:
* check if the Zephyr minimal C++ library is enabled using
`CONFIG_MINIMAL_LIBCPP` instead of relying on the
`CONFIG_LIB_CPLUSPLUS`-based inference.
* select `CONFIG_REQUIRES_FULL_LIBCPP` when there exists a component-
level C++ standard library dependency. This allows a component to
declare C++ standard library dependency without designating a
specific libray implementation.
* select the correct type of C++ standard library implementation to use
through one of the `CONFIG_LIBCPP_IMPLEMENTATION` choices.
Signed-off-by: Stephanos Ioannidis <stephanos.ioannidis@nordicsemi.no>
cf211aa7af