[mlir][doc] Fix reported Builtin (syntax) issues (#74635)

Fixes https://github.com/llvm/llvm-project/issues/62489.

Some notes for each number:

- 1 `bool-literal` should be reasonably clear from context.
- 2 Fixed.
- 3 This is now fixed. `loc(fused[])` is valid, but `loc(fused["foo",])`
is not.
- 4 This operation uses `assemblyFormat` so the syntax is correct
(assuming ODS is correct).
- 5 This operation uses `assemblyFormat` so the syntax is correct
(assuming ODS is correct).
- 6 Added an example.
- 7 The suggested fix is in line with other `assemblyFormat` examples.
- 8 Added syntax and an example.
- 9 I don't know what this is referring too.
- 10 Added example.
- 11 and 12 suggestion seems wrong as the `ShapedTypeInterface` could be
extended by clients, so is not limited to tensors or vectors.
- 13 is already reasonably clear with the example, I think.
- 14 is already reasonably clear with the example, I think.
- 15 Added an example from the `opaque_locations.mlir` tests.
- 16 The answer to this seems to change over time and depend on the use
case? Suggestions by reviewers are welcome.