board_f: Add a new struct to hold pre-relocation info

board_f: Add a new struct to hold pre-relocation info

Quite a few of the members of struct global_data are only used before
reloction, or have little meaning afterwards, yet they hang around in
struct global_data for the lifetime of U-Boot. This uses up precious
pre-relocation SRAM on many boards.

To help with this, start a new struct which exists only before
relocation. Move new_fdt into this new struct. Drop the display of it
in the 'bdinfo' command as it is probably not very useful.

Note that the field does not exist in SPL builds.

Signed-off-by: Simon Glass <sjg@chromium.org>