[MLIR][NFC] Fix build on recent GCC with C++20 enabled (#73308)

The following pattern fails on recent GCC versions with -std=c++20 flag
passed and succeeds with -std=c++17. Such behavior is not observed on
Clang 16.0.

```
template <typename T>
struct Foo {
    Foo<T>(int a) {}
};
```

This patch removes template parameter from constructor in two occurences
to make the following command complete successfully:
bazel build -c fastbuild --cxxopt=-std=c++20 --host_cxxopt=-std=c++20
@llvm-project//mlir/...

This patch is similar to https://reviews.llvm.org/D154782



Co-authored-by: Alexander Batashev <a.batashev@partner.samsung.com>