Add lowering linalg.for to LLVM IR

Add lowering linalg.for to LLVM IR

    This CL adds lowering of linalg.for to LLVM IR and adds an IR test.
    This also replaces the usage of affine.for with linalg.for and enables the LLVM IR path in the integration test.

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PiperOrigin-RevId: 250503798