Add dynamic interface casting to NN utility code

Prior to this CL, the NN utility code would always use the type of
IPreparedModel provided by IPreparedModeCallback::notify*. This means
that an IPreparedModel returned as a dynamic type of V1_X but static
type of V1_Y would be used by the utility code as V1_Y. This CL adds
dynamic casting, such that an IPreparedModel returned as a dynamic type
of V1_X but static type V1_Y will be dynamically cast to V1_X and used
as a V1_X::IPreparedModel.

This CL also adds the utility functions
V1_[0123]::convertFromNonCanonical to convert from a non-canonical type
to another non-canonical type by using canonical types as an
intermediate conversion "hop."

Bug: 178180472
Test: mma
Change-Id: I709b2a8944af2cc78b089aade55df1e2ab7b40cc
Merged-In: I709b2a8944af2cc78b089aade55df1e2ab7b40cc
(cherry picked from commit 49b5e4eb)