[PATCH v2] erofs-utils: Provide identical functionality without libuuid

[Gao Xiang]

On 2023/7/4 05:58, Norbert Lange wrote:
> The motivation is to have standalone (statically linked) erofs binaries
> for simple initrd images, that are nevertheless able to (re)create
> erofs images with a given UUID.
> 
> For this reason a few of libuuid functions have implementations added
> directly in erofs-utils.
> A header liberofs_uuid.h provides the new functions, which are
> always available. A further sideeffect is that code can be simplified
> which calls into this functionality.
> 
> The uuid_unparse function replacement is always a private
> implementation and split into its own file, this further restricts
> the (optional) dependency on libuuid only to the erofs-mkfs tool.
> 
> Signed-off-by: Norbert Lange <nolange79 at gmail.com>

I've rebased it on -dev branch (rather than other branches) and
apply it to experimental branch for testing.