[Static Runtime] Fix handling relu in quantized linear relu dynamic op
Summary:
The implementation of `PackedLinearWeightFp16::apply_dynamic_impl` [here](https://www.internalfb.com/code/fbsource/[b1ef7c31f022]/fbcode/caffe2/aten/src/ATen/native/quantized/cpu/qlinear_dynamic.cpp?lines=393) does not handle `relu`. It completely ignores the `ReluFused` boolean template parameter.
At this point, callers of that function handle `relu` explicitly. While the correct thing to do would be to handle the `ReluFused` parameter in that implementation, it is not clear if that semantics is being followed in this code. So, we are handling this in SR's out-variant implementation, until the owner fixes that issue.
This issue resulted in incorrect results when Static Runtime was enabled for the MRS video model.
Test Plan:
```
buck run mode/opt //caffe2/benchmarks/static_runtime:static_runtime_cpptest -- --gtest_filter=StaticRuntime.QuantizedLinearReluDynamicFp16
```
Reviewed By: mikeiovine
Differential Revision: D35366309
fbshipit-source-id: e60126e3590d52681ceaee5583b81c4c0b5404d9
(cherry picked from commit cabeb96a792339e7dbfd16cb51a3ac9039812137)
