chore(deps): upgrade memoffset to 0.6.5

`memoffset` with `unstable_const` feature depends on nightly compiler
features and thus is fragile against compiler upgrades, just like this
project. `memoffset 0.6.5` includes the changes from
[Gilnaa/memoffset#63], which updates it to support the latest nightly
compiler.

[Gilnaa/memoffset#63]: Gilnaa/memoffset#63

Author: yvt

Cargo.lock

@@ -18,7 +18,7 @@ r3_kernel = { version = "0.0.0", path = "../r3_kernel" }
 r3 = { version = "0.1.0", path = "../r3" }
 
 tock-registers = { version = "0.7.0" }
-memoffset = { version = "0.6.1", features = ["unstable_const"] }
+memoffset = { version = "0.6.5", features = ["unstable_const"] }
 r0 = { version = "1.0.0" }
 
 [package.metadata.docs.rs]

src/r3_port_arm/Cargo.toml

@@ -17,7 +17,7 @@ r3_portkit = { version = "0.1.1", path = "../r3_portkit" }
 r3_kernel = { version = "0.0.0", path = "../r3_kernel" }
 r3 = { version = "0.1.1", path = "../r3" }
 
-memoffset = { version = "0.6.1", features = ["unstable_const"] }
+memoffset = { version = "0.6.5", features = ["unstable_const"] }
 
 # `cortex-m-rt` doesn't build on a hosted target. We don't want
 # `cargo test --all` to fail because of this, so we put these in the