fix: reference to packed field is unaligned

[Taowyoo]

The main changes are in commit: fix: reference to packed field is unaligned
The other commit are code refactor to resolve some warning of deprecated macro or syntax.

[Taowyoo]

@jethrogb could you help reivew this PR?

[arai-fortanix]

This looks like it changes public interfaces, so is this an incompatible change to the crate?

[Taowyoo]

This looks like it changes public interfaces, so is this an incompatible change to the crate?

Yes, you are correct. Since I found the 0.2.0 is not published so I do not bump the version.
Will need some changes in https://github.com/fortanix/rust-sgx/blob/master/intel-sgx/sgxs-tools/src/bin/isgx-pe2sgx.rs for incompatible change here

[arai-fortanix]

I tried compiling this locally, and it also complained about the use of the bitflags! macro in src/types.rs using the deprecated try! macro. So the bitflags dependency also may need to be updated. That may require further source changes.

[arai-fortanix]

I'm wondering if we can just get rid of pe2sgxs though. Does anyone actually use it?

[Taowyoo]

I tried compiling this locally, and it also complained about the use of the bitflags! macro in src/types.rs using the deprecated try! macro. So the bitflags dependency also may need to be updated. That may require further source changes.

If update bitflags! to new version: >=1.0.0, the the new bitflags use some refrence in it's macro which cause compile error