Fix the "Failed to open random seed ..." message.
    
    When boot ArchLinux from Ventoy, it always print `Failed to open random seed file: write protected.`
    As Ventoy emulate the ISO file as a read-only CDROM, I didn't test with a real physical CDROM drive, but maybe it also has such problem.
    As we use `EFI_FILE_MODE_WRITE`  to open the `loader\random-seed` file, so I think it's better to check the result with both  `EFI_WRITE_PROTECTED` and `EFI_NOT_FOUND`.
    
    (cherry picked from commit 2846007ecfb1fc84005b942167d394294c707d7b)