dEQP tests up to 1024 for token length.
Fixes dEQP-GLES3.functional.shaders.uniform_block.valid.long_*

Change-Id: Iba2a79fc210e58e5681dd15a3cece3f8129d4d32
Reviewed-on: https://swiftshader-review.googlesource.com/14229Tested-by: Alexis Hétu <sugoi@google.com>
Reviewed-by: Nicolas Capens <nicolascapens@google.com>