board_f: show_dram_config: Print also real DRAM size
32-bit U-Boot builds cannot use more than around 2 GB of DDR memory. But on
some platforms/boards it is possible to connect also 4 GB SODIMM DDR memory.
U-Boot currently prints only effective size of RAM which can use, which may
be misleading as somebody would expect that this line prints total size of
connected DDR modules. So change show_dram_config code to prints both real
and effective DRAM size if they are different. If they are same then print
just one number like before. It is possible that effective size is just few
bytes smaller than the real size, so print both numbers only in case
function print_size() prints formats them differently.