fadump: fix default initrd backup and restore logic
    
    Resolves: bz2139000
    Upstream: Fedora
    Conflict: None
    
    commit 25411da9660e732a53e675936813aad924ba65df
    Author: Hari Bathini <hbathini@linux.ibm.com>
    Date:   Fri Dec 2 18:46:50 2022 +0530
    
        fadump: fix default initrd backup and restore logic
    
        In case of fadump, default initrd is rebuilt with dump capturing
        capability, as the same initrd is used for booting production kernel
        as well as capture kernel.
    
        The original initrd file is backed up with a checksum, to restore
        it as the default initrd when fadump is disabled. As the checksum
        file is not kernel version specific, switching between different
        kernel versions and kdump/fadump dump mode breaks the default initrd
        backup/restore logic. Fix this by having a kernel version specific
        checksum file.
    
        Also, if backing up initrd fails, retaining the checksum file isn't
        useful. Remove it.
    
        Signed-off-by: Hari Bathini <hbathini@linux.ibm.com>
        Reviewed-by: Philipp Rudo <prudo@redhat.com>
    
    Signed-off-by: Lichen Liu <lichliu@redhat.com>