drm/asahi: fw: Clippy fixes

Signed-off-by: Asahi Lina <[email protected]>

Author: hoshinolina

drivers/gpu/drm/asahi/fw/event.rs

@@ -52,6 +52,7 @@ pub(crate) mod raw {
     impl Default for NotifierState::ver {
         fn default() -> Self {
             #[allow(unused_mut)]
+            // SAFETY: All bit patterns are valid for this type.
             let mut s: Self = unsafe { core::mem::zeroed() };
             #[ver(V >= V13_0B4)]
             s.unk_buf = Array::new([0xff; 0x8]);

drivers/gpu/drm/asahi/fw/types.rs

@@ -53,6 +53,7 @@ pub(crate) struct FwStamp(pub(crate) AtomicU32);
 #[repr(C, packed(1))]
 pub(crate) struct U64(pub(crate) u64);
 
+// SAFETY: U64 is zeroable just like u64
 unsafe impl Zeroable for U64 {}
 
 impl fmt::Debug for U64 {
@@ -70,6 +71,7 @@ impl fmt::Debug for U64 {
 #[repr(C, packed(1))]
 pub(crate) struct U32(pub(crate) u32);
 
+// SAFETY: U32 is zeroable just like u32
 unsafe impl Zeroable for U32 {}
 
 impl fmt::Debug for U32 {