Add clang-tidy and splint static analytics check. For now, we use only
the cert-* warnings on clang-tidy and run splint with a lot of flags
to allow more things.
Changes to silence these analytics:
- Stop returning stuff from our debug print functions. We don't check
them anyway and we don't have any way of detecting transmission
failure.
- Declare more things static that isn't used outside of a file.
- Change types to be more consistent, typically to size_t or
something or to uint32_t.
Introduce memcpy_s() and wordcpy_s() that takes the destination buffer
size as an argument. Use assert() which aborts our program to an
eternal loop if we hit problems.
Sprinkle asserts elsewhere as well.
Signed-off-by: Daniel Lublin <daniel@lublin.se>
