[mlir][MLProgram][NFC] Migrate to OpAsmAttrInterface for ASM alias generation (#130481)

After the introduction of `OpAsmAttrInterface`, it is favorable to
migrate code using `OpAsmDialectInterface` for ASM alias generation,
which lives in `Dialect.cpp`, to use `OpAsmAttrInterface`, which lives
in `Attrs.td`. In this way, attribute behavior is placed near its
tablegen definition and people won't need to go through other files to
know what other (unexpected) hooks comes into play.

See #124721 for the interface itself and #128191 and #130479 for prior
migrations.

Note that `MLProgramOpAsmInterface` has no content now. However, if we
delete it, a failure related to dialect resource handling will occur

```
within split at llvm-project/mlir/test/IR/invalid-file-metadata.mlir:60 offset :7:7: error: unexpected error: unexpected 'resource' section for dialect 'ml_program'
```

To support resource such interface must be registered.

1 files changed, 0 insertions, 8 deletions

diff --git a/mlir/lib/Dialect/MLProgram/IR/MLProgramDialect.cpp b/mlir/lib/Dialect/MLProgram/IR/MLProgramDialect.cpp
index bda1032ed988..0b1561213165 100644
--- a/mlir/lib/Dialect/MLProgram/IR/MLProgramDialect.cpp
+++ b/mlir/lib/Dialect/MLProgram/IR/MLProgramDialect.cpp
@@ -39,14 +39,6 @@ struct MLProgramInlinerInterface : public DialectInlinerInterface {
 
 struct MLProgramOpAsmDialectInterface : public OpAsmDialectInterface {
   using OpAsmDialectInterface::OpAsmDialectInterface;
-
-  AliasResult getAlias(Attribute attr, raw_ostream &os) const override {
-    if (llvm::isa<ExternAttr>(attr)) {
-      os << "extern";
-      return AliasResult::OverridableAlias;
-    }
-    return AliasResult::NoAlias;
-  }
 };
 } // namespace