clif-util: Switch to using structopt for CLI arguments

cranelift/Cargo.toml

@@ -30,7 +30,6 @@ cranelift-simplejit = { path = "simplejit", version = "0.66.0" }
 cranelift-preopt = { path = "preopt", version = "0.66.0" }
 cranelift = { path = "umbrella", version = "0.66.0" }
 filecheck = "0.5.0"
-clap = "2.32.0"
 log = "0.4.8"
 term = "0.6.1"
 capstone = { version = "0.6.0", optional = true }
@@ -44,6 +43,7 @@ indicatif = "0.13.0"
 thiserror = "1.0.15"
 walkdir = "2.2"
 anyhow = "1.0.32"
+structopt = "0.3.17"
 
 [features]
 default = ["disas", "wasm", "cranelift-codegen/all-arch", "peepmatic-souper", "souper-harvest"]