Use clippy (#276)

* cton-util: fix some clippy unnecessary pass-by-value warnings

* clippy: ignore too many arguments / cyclomatic complexity in module

since these functions are taking args coming from the command line, i
dont think this is actually a valid lint, morally the arguments are all
from one structure

* cton-util: take care of remaining clippy warnings

* cton-reader: fix all non-suspicious clippy warnings

* cton-reader: disable clippy at site of suspicious lint

* cton-frontend: disable clippy at the site of an invalid lint

* cton-frontend: fix clippy warnings, or ignore benign ones

* clippy: ignore the camelcase word WebAssembly in docs

* cton-wasm: fix clippy complaints or ignore benign ones

* cton-wasm tests: fix clippy complaints

* cretonne: starting point turns off all clippy warnings

* cretonne: clippy fixes, or lower allow() to source of problem

* cretonne: more clippy fixes

* cretonne: fix or disable needless_lifetimes lint

this linter is buggy when the declared lifetime is used for another type
constraint.

* cretonne: fix clippy complaint about Pass::NoPass

* rustfmt

* fix prev minor api changes clippy suggested

* add clippy to test-all

* cton-filetests: clippy fixes

* simplify clippy reporting in test-all

* cretonne: document clippy allows better

* cretonne: fix some more clippy lints

* cretonne: fix clippy lints (mostly doc comments)

* cretonne: allow all needless_lifetimes clippy warnings

remove overrides at the false positives

* rustfmt

lib/cretonne/src/ir/extname.rs

@@ -16,7 +16,7 @@ const TESTCASE_NAME_LENGTH: usize = 16;
 /// to keep track of a sy mbol table.
 ///
 /// External names are primarily used as keys by code using Cretonne to map
-/// from a cretonne::ir::FuncRef or similar to additional associated data.
+/// from a `cretonne::ir::FuncRef` or similar to additional associated data.
 ///
 /// External names can also serve as a primitive testing and debugging tool.
 /// In particular, many `.cton` test files use function names to identify

lib/cretonne/src/ir/layout.rs

@@ -428,7 +428,7 @@ impl Layout {
     }
 
     /// Return an iterator over all EBBs in layout order.
-    pub fn ebbs<'f>(&'f self) -> Ebbs<'f> {
+    pub fn ebbs(&self) -> Ebbs {
         Ebbs {
             layout: self,
             next: self.first_ebb,
@@ -611,7 +611,7 @@ impl Layout {
     }
 
     /// Iterate over the instructions in `ebb` in layout order.
-    pub fn ebb_insts<'f>(&'f self, ebb: Ebb) -> Insts<'f> {
+    pub fn ebb_insts(&self, ebb: Ebb) -> Insts {
         Insts {
             layout: self,
             head: self.ebbs[ebb].first_inst.into(),