MLBEDSW-4838 Added basic TOSA support.

Added basic TOSA support, enabling Vela to
read and compile  a .tosa file corresponding to
CONV2D + Rescale + Clamp, and writing it to an
optimized .tflite file.

The optimized .tflite file, will in this case, hold
a commandstream where the Rescale and Clamp has been
fused into the CONV2D.

The optimized tflite file is not output from Vela.

  -Added support to read .tosa file into Vela
    internal structure.
      - Added tosa_reader.py, tosa_mapper.py and
        helper files stored under tosa/
      - Support for this limited to ~10 ops

    -Added reader_util.py for functions common
    for TOSA and TFLite

    -Added tosa_graph_optimiser.py
      -Added support to fuse Rescale into convolution
      -Modified handling for padding

    -Added support to fuse Clamp to previous op

    -Added graph_optimiser_util.py
      -Moved functions common for TOSA/TFLite graph
       optimization to this file.

    -Renamed graph_optimiser.py to tflite_graph_optmiser.py

    -Added separate tosa_supported_operators.py

    -Added supported_operator_util.py
       -For functions in common for TOSA/TFLite

Signed-off-by: Patrik Gustavsson <patrik.gustavsson@arm.com>
Change-Id: Ic3c540504ec8c5eb4771397fdc6882050ecf33ab
diff --git a/ethosu/vela/tosa/CondIfAttribute.py b/ethosu/vela/tosa/CondIfAttribute.py
new file mode 100644
index 0000000..bc19b95
--- /dev/null
+++ b/ethosu/vela/tosa/CondIfAttribute.py
@@ -0,0 +1,38 @@
+# automatically generated by the FlatBuffers compiler, do not modify
+
+# namespace: tosa
+
+import flatbuffers
+
+class CondIfAttribute(object):
+    __slots__ = ['_tab']
+
+    @classmethod
+    def GetRootAsCondIfAttribute(cls, buf, offset):
+        n = flatbuffers.encode.Get(flatbuffers.packer.uoffset, buf, offset)
+        x = CondIfAttribute()
+        x.Init(buf, n + offset)
+        return x
+
+    # CondIfAttribute
+    def Init(self, buf, pos):
+        self._tab = flatbuffers.table.Table(buf, pos)
+
+    # CondIfAttribute
+    def ThenBranch(self):
+        o = flatbuffers.number_types.UOffsetTFlags.py_type(self._tab.Offset(4))
+        if o != 0:
+            return self._tab.String(o + self._tab.Pos)
+        return None
+
+    # CondIfAttribute
+    def ElseBranch(self):
+        o = flatbuffers.number_types.UOffsetTFlags.py_type(self._tab.Offset(6))
+        if o != 0:
+            return self._tab.String(o + self._tab.Pos)
+        return None
+
+def CondIfAttributeStart(builder): builder.StartObject(2)
+def CondIfAttributeAddThenBranch(builder, thenBranch): builder.PrependUOffsetTRelativeSlot(0, flatbuffers.number_types.UOffsetTFlags.py_type(thenBranch), 0)
+def CondIfAttributeAddElseBranch(builder, elseBranch): builder.PrependUOffsetTRelativeSlot(1, flatbuffers.number_types.UOffsetTFlags.py_type(elseBranch), 0)
+def CondIfAttributeEnd(builder): return builder.EndObject()