linters: Fix clippy issues

Latest clippy version complains about our existing code for the
following reasons:

- trait objects without an explicit `dyn` are deprecated
- `...` range patterns are deprecated
- lint `clippy::const_static_lifetime` has been renamed to
  `clippy::redundant_static_lifetimes`
- unnecessary `unsafe` block
- unneeded return statement

All these issues have been fixed through this patch, and rustfmt has
been run to cleanup potential formatting errors due to those changes.

Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>

pci/src/bus.rs

@@ -192,8 +192,8 @@ impl BusDevice for PciConfigIo {
     fn read(&mut self, _base: u64, offset: u64, data: &mut [u8]) {
         // `offset` is relative to 0xcf8
         let value = match offset {
-            0...3 => self.config_address,
-            4...7 => self.config_space_read(),
+            0..=3 => self.config_address,
+            4..=7 => self.config_space_read(),
             _ => 0xffff_ffff,
         };
 
@@ -214,8 +214,8 @@ impl BusDevice for PciConfigIo {
     fn write(&mut self, _base: u64, offset: u64, data: &[u8]) {
         // `offset` is relative to 0xcf8
         match offset {
-            o @ 0...3 => self.set_config_address(o, data),
-            o @ 4...7 => self.config_space_write(o - 4, data),
+            o @ 0..=3 => self.set_config_address(o, data),
+            o @ 4..=7 => self.config_space_write(o - 4, data),
             _ => (),
         };
     }

pci/src/device.rs

@@ -18,7 +18,7 @@ pub struct InterruptParameters<'a> {
 }
 
 pub type InterruptDelivery =
-    Box<Fn(InterruptParameters) -> std::result::Result<(), std::io::Error> + Send + Sync>;
+    Box<dyn Fn(InterruptParameters) -> std::result::Result<(), std::io::Error> + Send + Sync>;
 
 #[derive(Debug)]
 pub enum Error {