[ref model] Change RescaleOp attrs to inputs

This patch implements changes required for RescaleOp's
multiplier and shift changing from attributes to inputs

Signed-off-by: Tai Ly <tai.ly@arm.com>
Change-Id: I178919727e3220c749dad0ebce141e695868fee0
diff --git a/verif/generator/tosa_utils.py b/verif/generator/tosa_utils.py
index 31a0ff0..384463f 100644
--- a/verif/generator/tosa_utils.py
+++ b/verif/generator/tosa_utils.py
@@ -55,6 +55,14 @@
     FIXED_DATA = 5
 
 
+def dtypeWidth(dtype):
+    """Get the datatype width for data types"""
+    if dtype in DTYPE_ATTRIBUTES:
+        return DTYPE_ATTRIBUTES[dtype]["width"]
+    else:
+        raise Exception(f"Unknown dtype, cannot determine width: {dtype}")
+
+
 def dtypeIsSupportedByCompliance(dtype):
     """Types supported by the new data generation and compliance flow."""
     if isinstance(dtype, list) or isinstance(dtype, tuple):