Add typedefs and defines to obfuscate the word hardware.

When the stack code is available, the word hardware
will be removed and these typedefs removed.

Hardware is a confusing word because the stack
is hardware indepedent. Its currently in the hardware
directory for convenience. Later on, we might move
the header files to a different location.

Change-Id: I4c456390d6003b7d02184bb6bcb2dd3b01c53485