Fix the shape of the outcome in the example code.

The toy language uses element-wise multiplication. Transposing and multiplying
two tensors with shape <2, 3> gives a tensor with shape <3, 2>.

Closes tensorflow/mlir#227

COPYBARA_INTEGRATE_REVIEW=tensorflow/mlir#227 from ombre5733:toy-ch1-docu-fix d79e5d3f9e3d5150a7ac8aac28b899df5a0d10a0
PiperOrigin-RevId: 281221671

mlir/g3doc/Tutorials/Toy/Ch-1.md

@@ -86,15 +86,15 @@ def main() {
   var b<2, 3> = [1, 2, 3, 4, 5, 6];
 
   # This call will specialize `multiply_transpose` with <2, 3> for both
-  # arguments and deduce a return type of <2, 2> in initialization of `c`.
+  # arguments and deduce a return type of <3, 2> in initialization of `c`.
   var c = multiply_transpose(a, b);
 
   # A second call to `multiply_transpose` with <2, 3> for both arguments will
-  # reuse the previously specialized and inferred version and return `<2, 2>`
+  # reuse the previously specialized and inferred version and return <3, 2>.
   var d = multiply_transpose(b, a);
 
-  # A new call with `<2, 2>` for both dimensions will trigger another
-  # specialization of `multiply_transpose`.
+  # A new call with <3, 2> (instead of <2, 3>) for both dimensions will
+  # trigger another specialization of `multiply_transpose`.
   var e = multiply_transpose(c, d);
 
   # Finally, calling into `multiply_transpose` with incompatible shape will