[mlir][linalg] Enable pack consumer fusion for all perfect tiling cases. (#150672)
It was disabled because there may be artificial padding. After [refining the pack op semantics](https://github.com/llvm/llvm-project/commit/773e158c64735a80b814f20be6b959d9577531f8),
we can assume that there is no artificial padding. Thus, the check can
be removed, and we can unconditionally enable the consumer fusion if it
is a perfect tiling case.
Signed-off-by: hanhanW <hanhan0912@gmail.com>