Upgrade to Rust 1.17.

- Remove some uses of 'static in const and static globals that are no
  longer needed.
- Use the new struct initialization shorthand.

lib/cretonne/src/isa/arm32/mod.rs

@@ -39,7 +39,7 @@ fn isa_constructor(shared_flags: shared_settings::Flags,
     };
     Box::new(Isa {
                  isa_flags: settings::Flags::new(&shared_flags, builder),
-                 shared_flags: shared_flags,
+                 shared_flags,
                  cpumode: level1,
              })
 }

lib/cretonne/src/isa/arm64/mod.rs

@@ -33,7 +33,7 @@ fn isa_constructor(shared_flags: shared_settings::Flags,
                    -> Box<TargetIsa> {
     Box::new(Isa {
                  isa_flags: settings::Flags::new(&shared_flags, builder),
-                 shared_flags: shared_flags,
+                 shared_flags,
              })
 }
 

lib/cretonne/src/isa/encoding.rs

@@ -19,10 +19,7 @@ pub struct Encoding {
 impl Encoding {
     /// Create a new `Encoding` containing `(recipe, bits)`.
     pub fn new(recipe: u16, bits: u16) -> Encoding {
-        Encoding {
-            recipe: recipe,
-            bits: bits,
-        }
+        Encoding { recipe, bits }
     }
 
     /// Get the recipe number in this encoding.

lib/cretonne/src/isa/intel/mod.rs

@@ -39,7 +39,7 @@ fn isa_constructor(shared_flags: shared_settings::Flags,
     };
     Box::new(Isa {
                  isa_flags: settings::Flags::new(&shared_flags, builder),
-                 shared_flags: shared_flags,
+                 shared_flags,
                  cpumode: level1,
              })
 }

lib/cretonne/src/isa/registers.rs

@@ -220,7 +220,7 @@ impl RegInfo {
     /// Make a temporary object that can display a register unit.
     pub fn display_regunit(&self, regunit: RegUnit) -> DisplayRegUnit {
         DisplayRegUnit {
-            regunit: regunit,
+            regunit,
             reginfo: self,
         }
     }

lib/cretonne/src/isa/riscv/mod.rs

@@ -39,7 +39,7 @@ fn isa_constructor(shared_flags: shared_settings::Flags,
     };
     Box::new(Isa {
                  isa_flags: settings::Flags::new(&shared_flags, builder),
-                 shared_flags: shared_flags,
+                 shared_flags,
                  cpumode: level1,
              })
 }