Misaligned pointer dereference in sa_in and sa_in6

[shinmao]

The source of unsoundness

Hi, we found that two safe functions created misaligned pointers and dereference:

if-addrs/src/sockaddr.rs

Lines 99 to 108 in 947c634

	#[allow(unsafe_code)]
	#[allow(clippy::cast_ptr_alignment)]
	fn sa_in(&self) -> sockaddr_in {
	unsafe { *(self.inner.as_ptr() as *const sockaddr_in) }
	}
	#[allow(unsafe_code)]
	#[allow(clippy::cast_ptr_alignment)]
	fn sa_in6(&self) -> sockaddr_in6 {
	unsafe { *(self.inner.as_ptr() as *const sockaddr_in6) }

At line 102 and 108, they both cast the type aligned to 2 bytes to the type aligned to 4 bytes. This could lead to undefined behavior in safe functions.