Update Rust crate num_enum to 0.7.5 (#143)

Co-authored-by: oxide-renovate[bot] <146848827+oxide-renovate[bot]@users.noreply.github.com>

Author: oxide-renovate[bot]

Cargo.lock

@@ -20,7 +20,7 @@ nvpair-sys = { git = "https://github.com/jmesmon/rust-libzfs", branch = "master"
 #nvpair-sys = "0.4"
 
 dlpi = { git = "https://github.com/oxidecomputer/dlpi-sys", default-features = false }
-num_enum = "0.7.4"
+num_enum = "0.7.5"
 oxnet = { version = "0.1.3", default-features = false }
 rusty-doors = { git = "https://github.com/oxidecomputer/rusty-doors" }
 rand = "0.9.2"