Add soname

### Problem:

Would like to package this for Fedora. For shared libraries, it is helpful to have a soname. Would a pull request to add a soname be required.

### Solution:

Add soname in CMake configuration for shared library builds

* **Does this change any public APIs?*** If yes, explain.
Does not change any APIs, though when using shared library, linking to an explicit version will be made easier.

* **Which algorithm(s) will this impact?**
Does not change any algorithms.

### Requirements / Acceptance Criteria:

What must a solution address in order to solve the problem? How do we know the solution is complete?
Shared libraries should have sonames, should generate .so, .so.x and .so.x.x.x - may want to use the sonames used for libssl and libcrypto used by the associated boringssl library if expect to keep compatibility, otherwise use sonames based on aws-lc releases

* **RFC links:** No relevant RFCs
* **Related Issues:** Link any relevant issues
* **Will the Usage Guide or other documentation need to be updated?** No changes needed
* **Testing:** No changes to tests needed.
* **Will this change trigger AWS LibCrypto Formal Verification changes?** No changes needed
* **Should this change be fuzz tested?** No changes needed

### Out of scope:

Is there anything the solution will intentionally NOT address?