kdumpctl: Drop default kexec '-d' option
    
    Resolves: RHEL-39494
    Conflicts: Small difference in context of 2nd hunk.
    
    commit 3028529915d3026e62b59d8f3faadddd410baa75
    Author: Philipp Rudo <prudo@redhat.com>
    Date:   Fri Jun 14 11:48:24 2024 +0200
    
        kdumpctl: Drop default kexec '-d' option
    
        Kernel commits cbc2fe9d9cb2 ("kexec_file: add kexec_file flag to control
        debug printing") and a85ee18c7900 ("kexec_file: print out debugging
        message if required") added debug messages to the kexec_file_load system
        call when option -d is provided to the kexec user space tool. As
        kexec_file_load is the default and option -d is set by default these
        messages are always printed when a crash kernel is loaded. This not only
        clutters the kernel log but also potentially leaks confidential kernel
        information to users. As the messages are printed to the kernel log, not
        stderr, the redirection to /var/log/kdump.log won't catch them. This
        will become even more problematic as for RHEL10 the kernel will be built
        without support for the kexec_load system call. So kexec_file_load will
        be the only choice in the future.
    
        The redirection also caused confusion in a recent bug report. There a
        user moved a working /etc/sysconfig/kdump from ppc to s390 with
        KEXEC_ARGS containing the --dt-no-old-root option. This option is arch
        specific and does not exist on s390. Thus the kexec-tools failed with an
        'unrecognized option' error followed by the usage(). The problem was
        that the 'unrecognized option' error is printed to stderr, which got
        redirected to /var/log/kdump.log, while the usage() is printed to
        stdout, which ended up in the systemd journal. This caused confusion as
        the user only checked the journal and found the usage() without any
        error message.
    
        Thus remove the default -d option and the redirection of stderr to
        /var/log/kdump.log for the kexec-tools user space tool.
    
        This commit ultimately reverts 88a8b94 ("kdumpctl: add the '-d' option to
        enable the kexec loading debugging messages").
    
        Signed-off-by: Philipp Rudo <prudo@redhat.com>
    
    Signed-off-by: Philipp Rudo <prudo@redhat.com>