[serialization_lib] Remove unused type field from Pad and Clamp

This patch removes the "type" field from PadAttribute and ClampAttribute
because they are unused and unneeded.

Signed-off-by: Tai Ly <tai.ly@arm.com>
Change-Id: I378291b340ecee86824f25b3887aa4511207db23
diff --git a/include/attribute.def b/include/attribute.def
index 30b432d..723543e 100644
--- a/include/attribute.def
+++ b/include/attribute.def
@@ -52,9 +52,8 @@
               bool,    S, local_bound,
               DType,   S, acc_type)
 
-DEF_ATTRIBUTE(Pad, 2,
-              uint8_t, V, pad_const,
-              DType,   S, type)
+DEF_ATTRIBUTE(Pad, 1,
+              uint8_t, V, pad_const)
 
 DEF_ATTRIBUTE(Axis, 1,
               int32_t, S, axis)
@@ -65,10 +64,9 @@
               int16_t, V, border,
               ResizeMode, S, mode)
 
-DEF_ATTRIBUTE(Clamp, 3,
+DEF_ATTRIBUTE(Clamp, 2,
               uint8_t, V, min_val,
-              uint8_t, V, max_val,
-              DType,   S, type)
+              uint8_t, V, max_val)
 
 DEF_ATTRIBUTE(Rescale, 7,
               int32_t, S, input_zp,