crashkernel: Add ttyS0 console

Add "console=ttyS0,115200n8" to crashkernel commandline as we did for
the regular kernel in mxgrub. Also specifiy full command line here
instead of appending to the command line of the crashing kernel to get a
better defined state.

misc_systemd_units/crashkernel.service

@@ -6,7 +6,7 @@ ConditionPathExists=/boot/bzImage.crash
 StandardOutput=kmsg
 StandardError=kmsg
 Type=oneshot
-ExecStart=/usr/sbin/kexec -p /boot/bzImage.crash --initrd=/boot/grub/initramfs.igz "--append=root=LABEL=root ro console=ttyS1,115200n8 console=tty0 irqpoll maxcpus=1 reset_devices CRASH"
+ExecStart=/usr/sbin/kexec -p /boot/bzImage.crash --initrd=/boot/grub/initramfs.igz --command-line="root=LABEL=root ro console=ttyS0,115200n8 console=ttyS1,115200n8 console=tty0 irqpoll maxcpus=1 reset_devices CRASH"
 RemainAfterExit=yes
 
 [Install]