deps: Update libfuzzer-sys to 0.3.3 (#2072)

This update gives us access to the new Entropic fuzzing engine:
https://mboehme.github.io/paper/FSE20.Entropy.pdf

Author: fitzgen

Cargo.lock

@@ -12,7 +12,7 @@ cargo-fuzz = true
 cranelift-codegen = { path = "../cranelift/codegen" }
 cranelift-reader = { path = "../cranelift/reader" }
 cranelift-wasm = { path = "../cranelift/wasm" }
-libfuzzer-sys = "0.3.2"
+libfuzzer-sys = "0.3.3"
 target-lexicon = "0.10"
 peepmatic-fuzzing = { path = "../cranelift/peepmatic/crates/fuzzing", optional = true }
 wasmtime = { path = "../crates/wasmtime" }