[llvm] [clang-tools-extra] [mlir] [clang] [mlir][docs] Clarified Dialect creation tutorial + fixed typos (PR #77820)

[Mehdi Amini via cfe-commits]

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@@ -106,6 +106,12 @@ the LINK_COMPONENTS descriptor.  This allows cmake infrastructure to
 generate new library targets with correct linkage, in particular, when
 BUILD_SHARED_LIBS=on or LLVM_LINK_LLVM_DYLIB=on are specified.
 
+Registration of the dialect can be performed globally by editing the
+file include/mlir/InitAllDialects.h.  In this example, we can add
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joker-eph wrote:

This is framed as if it is a possibility: I believe this isn't optional, all dialects should be there.

https://github.com/llvm/llvm-project/pull/77820