[clang-tools-extra] [mlir] [NFC][MLIR] Fix some typos (PR #108355)

[Matthias Springer via cfe-commits]

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@@ -16,7 +16,7 @@ like Toy to get the information they need.
 
 MLIR provides a set of always available-hooks for certain core transformations,
 as seen in the [previous chapter](Ch-3.md), where we registered some
-canonicalizations via a hook on our operations (`getCanonicalizationPatterns`).
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matthias-springer wrote:

Not sure if `canonicalization` has a plural. In practice we often say `canonicalizations` though.

https://github.com/llvm/llvm-project/pull/108355