fix(hal-x86_64): don't log every MSR read

This was a stupid thing to do, and I only did it because I was being
excessively cutesy. Now that we read the FS_GS_BASE MSR in ISRs to
access local data, this can deadlock the kernel :upside_down:

hal-x86_64/src/cpu/msr.rs

@@ -281,9 +281,7 @@ impl<V> Msr<V> {
                 options(nomem, nostack, preserves_flags)
             );
         }
-        let result = (hi as u64) << 32 | (lo as u64);
-        tracing::trace!(rdmsr = %self, value = fmt::hex(result));
-        result
+        (hi as u64) << 32 | (lo as u64)
     }
 
     /// Writes the given raw `u64` value to this MSR.