Handling proper sampler types

Some int/uint/array types weren't properly handled by
the Program class yet, so the missing types were added.

Change-Id: I487bbbdcbf798c7430535745386139632346013f
Reviewed-on: https://swiftshader-review.googlesource.com/3610
Tested-by: Alexis Hétu <sugoi@google.com>
Reviewed-by: Nicolas Capens <capn@google.com>