Mike Leany

Compilation fails when `i128` and `u128` aren't supported. For example, when compiling a crate with these options: `-Z build-std=core,alloc,compiler_builtins --target=x86_64-unknown-uefi`. ``` error[E0407]: method `from_i128` is not a member of trait...

Implements the following conversions: - `TryFrom` for `VirtAddr` and `PhysAddr` - `TryFrom` for `VirtAddr` and `PhysAddr` - `From` for `VirtAddr` and `PhysAddr` - `TryFrom` for `VirtAddr` - `TryFrom` for `VirtAddr`...