We rely on the include path to find many of these headers. It
especially doesn't make sense to use #include "foo.h" for headers
in the top-level include directory.
The format value has to be a string literal, every time.
Otherwise, you are not using these functions correctly. To reinforce this fact, I putrestrict over every non-contrib example of this I could find.
Previously we needed to include headers required by the various
sudo*h files. Now those files are more self-sufficient and we
should only include headers needed by code in the various .c files.
