[MLIR][TOSA] Expand Tosa int types to I8 and I16

[rsuderman]

Summary

Tosa integers should include I8 and I16 values.

mlir/include/mlir/Dialect/Tosa/IR/TosaTypesBase.td

string asTraitArgsStr = !interleave(params, ", ") #
                           !if(signed, ", true", ", false");
 }
 
 //===----------------------------------------------------------------------===//
 // Non-Quantized Signed Integer Types.
 // Used to express accumulator results or compare results.
 //===----------------------------------------------------------------------===//
 
+def Tosa_Int8 : I<8>;
+def Tosa_Int16 : I<16>;
 def Tosa_Int32 : I<32>;
 def Tosa_Int48 : I<48>;
 def Tosa_Int64 : I<64>;
 
-def Tosa_SignedInt : AnyTypeOf<[Tosa_Int32,
+def Tosa_SignedInt : AnyTypeOf<[Tosa_Int8,
+                                Tosa_Int16,
+                                Tosa_Int32,
                                 Tosa_Int48,
                                 Tosa_Int64]>;
 
 def Tosa_Bool : I<1>;
 
 // No unsigned unquantized int types.
 def Tosa_Int : AnyTypeOf<[Tosa_Bool,
                           Tosa_SignedInt]>;