Add ttmlir-translate docs and cpp gen example (#152)

* add `ttmlir-translate` docs and cpp gen example

* add piped version

docs/src/SUMMARY.md

@@ -8,6 +8,7 @@
   - [Internal Build Notes / IRD](./internal-build.md)
 - [Tools](./tools.md)
   - [ttmlir-opt](./ttmlir-opt.md)
+  - [ttmlir-translate](./ttmlir-translate.md)
   - [ttrt](./ttrt.md)
 - [Flatbuffers](./flatbuffers.md)
 - [Additional Reading](./additional-reading.md)

docs/src/ttmlir-translate.md

@@ -0,0 +1,17 @@
+# `ttmlir-translate`
+
+The `ttmlir-translate` translation utility. Unlike `ttmlir-opt` tool which is used to run passes within the MLIR world, `ttmlir-translate` allows us to ingest something (e.g. code) into MLIR world, and also produce something (e.g. executable binary, or even code again) from MLIR.
+## Generate C++ code from MLIR
+
+```bash
+# First, let's run `ttmlir-opt` to convert to proper dialect
+./build/bin/ttmlir-opt --ttir-layout --ttnn-open-device --convert-ttir-to-ttnn --convert-ttnn-to-emitc test/ttmlir/Dialect/TTNN/simple_multiply.mlir -o c.mlir
+
+# Now run `ttmlir-translate` to produce C++ code
+./build/bin/ttmlir-translate -mlir-to-cpp c.mlir -allow-unregistered-dialect
+```
+
+Bonus: These two commands can be piped, to avoid writing a `mlir` file to disk, like so:
+```bash
+./build/bin/ttmlir-opt --ttir-layout --ttnn-open-device --convert-ttir-to-ttnn --convert-ttnn-to-emitc test/ttmlir/Dialect/TTNN/simple_multiply.mlir | ./build/bin/ttmlir-translate -mlir-to-cpp -allow-unregistered-dialect
+```