Fix remaining clippy warnings

Author: phil-opp

src/addr.rs

@@ -461,15 +461,15 @@ mod tests {
         // align 1
         assert_eq!(align_up(0, 1), 0);
         assert_eq!(align_up(1234, 1), 1234);
-        assert_eq!(align_up(0xffffffffffffffff, 1), 0xffffffffffffffff);
+        assert_eq!(align_up(0xffff_ffff_ffff_ffff, 1), 0xffff_ffff_ffff_ffff);
         // align 2
         assert_eq!(align_up(0, 2), 0);
         assert_eq!(align_up(1233, 2), 1234);
-        assert_eq!(align_up(0xfffffffffffffffe, 2), 0xfffffffffffffffe);
+        assert_eq!(align_up(0xffff_ffff_ffff_fffe, 2), 0xffff_ffff_ffff_fffe);
         // address 0
         assert_eq!(align_up(0, 128), 0);
         assert_eq!(align_up(0, 1), 0);
         assert_eq!(align_up(0, 2), 0);
-        assert_eq!(align_up(0, 0x8000000000000000), 0);
+        assert_eq!(align_up(0, 0x8000_0000_0000_0000), 0);
     }
 }

src/structures/paging/mapper/mapped_page_table.rs

@@ -479,7 +479,7 @@ impl<P: PhysToVirt> PageTableWalker<P> {
 
         let page_table = match self.next_table_mut(entry) {
             Err(PageTableWalkError::MappedToHugePage) => {
-                Err(PageTableCreateError::MappedToHugePage)?
+                return Err(PageTableCreateError::MappedToHugePage);
             }
             Err(PageTableWalkError::NotMapped) => panic!("entry should be mapped at this point"),
             Ok(page_table) => page_table,

src/structures/paging/page.rs

@@ -339,11 +339,11 @@ mod tests {
         let page_size = Size4KiB::SIZE;
         let number = 1000;
 
-        let start_addr = VirtAddr::new(0xdeadbeaf);
+        let start_addr = VirtAddr::new(0xdead_beaf);
         let start: Page = Page::containing_address(start_addr);
-        let end = start.clone() + number;
+        let end = start + number;
 
-        let mut range = Page::range(start.clone(), end.clone());
+        let mut range = Page::range(start, end);
         for i in 0..number {
             assert_eq!(
                 range.next(),