Use newtypes for PAddr and VAddr
Use newtypes for PAddr and VAddr

This provides some extra type safety by providing explicit constructions
and conversions of the PAddr and VAddr types. No runtime overhead.

Signed-off-by: Dan Schatzberg <2fd18fbc94e1d251ef5884a6fa05a98ae57788ae@gmail.com>

rexlunae/redox,rexlunae/redox,gz/rust-x86,rexlunae/redox,phil-opp/rust-x86_64,gz/rust-x86