Linux ICD loader version

[bashbaug]

PR #226 changed the ICD loader version on Linux slightly, see: c2cbdb3#diff-1e7de1ae2d059d21e1dd75d5812d5a34b0222cef273b7c3a2af62eb747f9d20aR124

Specifically, we used to build an OpenCL ICD loader with version 1.2 and soversion 1, and now we're building a file with version 1.0.0 and soversion 1. This isn't wrong per se, and the soversion is still 1 which is the most critical, but it could still be confusing since the version number went "backwards".

What version should we use for the ICD loader? Do we want to stay with 1.2, or 1.0.0?

Regardless, when we make changes and add features, should we increment the minor version or patch version?

Are there any concerns about conflicts with ocl-icd, which is also versioned 1.0.0?

Note, we shouldn't modify the soversion with a lot more thought, since this is where things will most likely break.

See also discussion here: #182 (comment)