This PR adds the Vector transfer_read to load rewrite pattern. The
pattern creates a transfer read op lowering. A vector trasfer read op
will be lowered to a combination of `vector.load`, `arith.select` and
`vector.broadcast` if:
- The transfer op is masked.
- The memref is in buffer address space.
- Other conditions introduced from `TransferReadToVectorLoadLowering`
The motivation of this PR is due to the lack of support of masked load
from amdgpu backend. `llvm.intr.masked.load` lower to a series of
conditional scalar loads refer to (`scalarize-masked-mem-intrin` pass).
This PR will make it possible for masked transfer_read to be lowered
towards buffer load with bounds check, allowing a more optimized global
load accessing pattern compared with existing implementation of
`llvm.intr.masked.load` on vectors.
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