arm64: zynqmp: Disable LMB for mini configurations

There is no need to have LMB enabled that's why save some space by
disabling it.

   aarch64: (for 8/8 boards) all -1168.5 rodata -105.5 text -1063.0
            xilinx_zynqmp_mini: all -2013 rodata -185 text -1828
            xilinx_zynqmp_mini_qspi: all -2013 rodata -185 text -1828
            xilinx_zynqmp_mini_emmc0: all -2661 rodata -237 text -2424
            xilinx_zynqmp_mini_emmc1: all -2661 rodata -237 text -2424

Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Michal Simek <michal.simek@amd.com>
Link: https://lore.kernel.org/r/f735d7691f4e7a7958d985b22c40aeb26e37a404.1657183534.git.michal.simek@amd.com