xenserver fix vm bootloader error

xe vm-param-set uuid=[vm-uuid] PV-bootloader-args=”–kernel=/boot/vmlinuz-3.10.0-123.4.2.el7.x86_64 –ramdisk=/boot/initramfs-3.10.0-123.4.2.el7.x86_64.img”

xe vm-param-set uuid=[vm-uuid] PV-args=”root=UUID=[root-uuid] ro quiet”