Translator checks tessellation shader unsized array type qualifier.
sample in/sample out were missing in handling qualifier type.

Bug: angleproject:5557
Test: GLSLTest_ES31.VaryingTessellationSampleInAndOut*
Change-Id: I8a2f2c4c4fcc9cc88000d3b2d448ab51fb9e5d38
Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/2776263Reviewed-by: Shahbaz Youssefi <syoussefi@chromium.org>
Reviewed-by: Jamie Madill <jmadill@chromium.org>
Commit-Queue: Mohan Maiya <m.maiya@samsung.com>