cksum: remove unneeded hex dependency

Cargo.lock

@@ -3126,7 +3126,6 @@ dependencies = [
  "clap",
  "codspeed-divan-compat",
  "fluent",
- "hex",
  "tempfile",
  "uucore",
 ]

fuzz/Cargo.lock

@@ -1575,7 +1575,6 @@ version = "0.5.0"
 dependencies = [
  "clap",
  "fluent",
- "hex",
  "uucore",
 ]
 

src/uu/cksum/Cargo.toml

@@ -25,7 +25,6 @@ uucore = { workspace = true, features = [
   "sum",
   "hardware",
 ] }
-hex = { workspace = true }
 fluent = { workspace = true }
 
 [dev-dependencies]

src/uu/cksum/src/cksum.rs

@@ -22,7 +22,7 @@ use uucore::checksum::{
 use uucore::error::UResult;
 use uucore::hardware::{HasHardwareFeatures as _, SimdPolicy};
 use uucore::line_ending::LineEnding;
-use uucore::{format_usage, translate};
+use uucore::{format_usage, show_error, translate};
 
 /// Print CPU hardware capability detection information to stderr
 /// This matches GNU cksum's --debug behavior
@@ -31,9 +31,9 @@ fn print_cpu_debug_info() {
 
     fn print_feature(name: &str, available: bool) {
         if available {
-            eprintln!("cksum: using {name} hardware support");
+            show_error!("using {name} hardware support");
         } else {
-            eprintln!("cksum: {name} support not detected");
+            show_error!("{name} support not detected");
         }
     }