[mlir][docs] Fix broken docs (#82308)

- Fixed OpenACC's spec link format
- Add missed `OpenACCPasses.md` into Passes.md
- Add missed `MyExtensionCh4.md` into Ch4.md of tutorial of transform

Author: sott0n

mlir/docs/Dialects/OpenACCDialect.md

@@ -9,8 +9,8 @@ by giving the compiler the freedom of how to parallelize for specific
 architectures. OpenACC also provides the ability to optimize the
 parallelism through increasingly more prescriptive clauses.
 
-This dialect models the constructs from the [OpenACC 3.3 specification]
-(https://www.openacc.org/sites/default/files/inline-images/Specification/OpenACC-3.3-final.pdf)
+This dialect models the constructs from the 
+[OpenACC 3.3 specification](https://www.openacc.org/sites/default/files/inline-images/Specification/OpenACC-3.3-final.pdf)
 
 This document describes the design of the OpenACC dialect in MLIR. It
 lists and explains design goals and design choices along with their
@@ -451,3 +451,4 @@ dominates another.
 ## Operations TOC
 
 [include "Dialects/OpenACCDialectOps.md"]
+

mlir/docs/Passes.md

@@ -16,6 +16,10 @@ This document describes the available MLIR passes and their contracts.
 
 [include "ConversionPasses.md"]
 
+## 'acc' Dialect Passes
+
+[include "OpenACCPasses.md"]
+
 ## 'affine' Dialect Passes
 
 [include "AffinePasses.md"]

mlir/docs/Tutorials/transform/Ch4.md

@@ -579,3 +579,7 @@ accessed dimensions as other parameters that can be compared with each other to
 ensure the subscripts are `m,k` for LHS, `k,n` for RHS and `m,n` for the
 init/result given the `m,n,k` notation for loops.
 
+## Appendix: Autogenerated Documentation
+
+[include "Tutorials/transform/MyExtensionCh4.md"]
+