Fix misaligned addresses while reading tensor attributes from raw data buffers (#27312)
### Description
Explicitly copy tensor attribute values from raw data buffers instead of
directly using pointers without checking proper memory alignment.
### Motivation and Context
Fixes #27311
With some (rare) models ONNXRuntime built for Android armeabi-v7a 32 bit
architecture crashes with bus error. Raw data buffers for tensor
attributes of type `char*` has no proper alignment guarantees while
reading values from them.
Actually, it is in general (not only Android armeabi-v7a) UB to access
objects at a misaligned address in C++, though many modern platforms
allow it.