fix: C standard requires prototype

[dawesc]

The latest compilers require all C functions to have a prototype to compile; adds the void prototype to those functions requiring this

Issue #805

Description of changes:
Added void to the prototypes of methods requiring this to allow the application to build on latest versions of clang

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.

Check any applicable:

• Were any files moved? Moving files changes their URL, which breaks all hyperlinks to the files.

[texastony]

Copying some CodeBuild test logs:
From build_test_dynamic:

43/43 Test #4: static_test_vectors ........................***Failed 204.96 sec 

Decryption successfully completed for 8208 test cases and failed for 1. 

I will kick off a retry for build_test_dynamic.

The other CodeBuild builds passed:

• build_test_static_debug
• build_test_static_valgrind
• compliance

The retry of build_test_dynamic succeeded, but the GitHub webhook will not refresh the the batch status.

[dawesc]

I've changed the comment to force a recompile to see if it will go through this time