[mlir][Transforms] Dialect Conversion: Simplify block-inline handling (#145308)

When a block is getting inlined, the destination block does not have to
be legalized. That's because the signature of the destination block does
not change by inlining.

This commit makes the implementation consistent with this comment:
```
  // If the pattern moved or created any blocks, make sure the types of block
  // arguments get legalized.
```

Author: matthias-springer

mlir/lib/Transforms/Utils/DialectConversion.cpp

@@ -2301,7 +2301,7 @@ LogicalResult OperationLegalizer::legalizePatternBlockRewrites(
       continue;
     Block *block = rewrite->getBlock();
     if (isa<BlockTypeConversionRewrite, EraseBlockRewrite,
-            ReplaceBlockArgRewrite>(rewrite))
+            ReplaceBlockArgRewrite, InlineBlockRewrite>(rewrite))
       continue;
     // Only check blocks outside of the current operation.
     Operation *parentOp = block->getParentOp();