[nrf noup] Bluetooth: Temporarily add C++ over internal header file

[rugeGerritsen]

This unblocks a specific use case where this header file is included.

[alwa-nordic]

I have verified keys.h is correct C++ (with GNU extension for zero-sized arrays).

[nordicjm]

why can this not be upstreamed?

[carlescufi]

Agreed, the overhead of doing a fromlist here i negligible? it's a trivial patch

[rugeGerritsen]

@nordicjm , @carlescufi We do not want to have a C++ header guard in this file upstream. Already agreed upon with the Bluetooth maintainer @alwa-nordic . This change is also temporary because we intend to provide a public API solving the customers request

[nordicjm]

@nordicjm , @carlescufi We do not want to have a C++ header guard in this file upstream. Already agreed upon with the Bluetooth maintainer @alwa-nordic . This change is also temporary because we intend to provide a public API solving the customers request

Then in the file that needs it do:

#ifdef __cplusplus
extern "C" {
#endif

#include <file/path/.c>

#ifdef __cplusplus
}
#endif

This as a hack temp. no-up is absolutely ridiculous

[rugeGerritsen]

@nordicjm , this has already been discussed internally with the maintainer.