Update clippy settings and fix a few clippy warnings.

lib/codegen/meta/src/constant_hash.rs

@@ -18,8 +18,7 @@ pub fn generate_table<T, H: Fn(&T) -> usize>(items: &Vec<T>, hash_function: H) -
         size.next_power_of_two()
     };
 
-    let mut table: Vec<Option<&T>> = Vec::new();
-    table.resize(size, None);
+    let mut table: Vec<Option<&T>> = vec![None; size];
 
     for i in items {
         let mut h = hash_function(i) % size;

lib/codegen/meta/src/gen_settings.rs

@@ -355,8 +355,7 @@ fn gen_descriptors(group: &SettingGroup, fmt: &mut Formatter) {
 }
 
 fn gen_template(group: &SettingGroup, fmt: &mut Formatter) {
-    let mut default_bytes: Vec<u8> = Vec::new();
-    default_bytes.resize(group.settings_size as usize, 0);
+    let mut default_bytes: Vec<u8> = vec![0; group.settings_size as usize];
     for setting in &group.settings {
         *default_bytes.get_mut(setting.byte_offset as usize).unwrap() |= setting.default_byte();
     }