console=hvc0 must be last

https://github.com/QubesOS/qubes-issues/issues/5490#issuecomment-562263712

misc/grub.qubes

@@ -2,7 +2,7 @@
 # same fs, including UUID
 GRUB_DISABLE_LINUX_UUID=true
 GRUB_DISABLE_OS_PROBER=true
-GRUB_CMDLINE_LINUX="$GRUB_CMDLINE_LINUX root=/dev/mapper/dmroot console=hvc0 console=tty0"
+GRUB_CMDLINE_LINUX="$GRUB_CMDLINE_LINUX root=/dev/mapper/dmroot console=tty0 console=hvc0"
 # make SWIOTLB smaller - it isn't really needed unless PCI passthrough is used,
 # and even then, 16MB is enough
 GRUB_CMDLINE_LINUX="$GRUB_CMDLINE_LINUX swiotlb=8192"