fix Issue 10947 - const out parameter is not properly rejected

Bitwise-and of Type::mod vs STCxxx is merely a mistake.

Additionally, `out inout` parameter should also be rejected.
[Refactoring] Report errors in semantic phase for invalid combination of parameter storage classes

Do it in parsing phase reduces the chance of error reporting.
Merge pull request #2511 from 9rnsr/fix10947

Issue 10947 - const out parameter is not properly rejected