carray_to_bytea?

I'd like to propose a carray_to_bytea function, similar to
cstring_to_text_with_len, declared in src/include/utils.h and implemented
in src/backend/utils/adt/varlena.c. The implementation would be the same
as cstring_to_text_with_len, but with a different return type.

I have put the implementation in my code, but I'd much prefer to use a
public API with hidden implementation.

Sound good?