rockchip: puma: fix GPT table corruption when saving U-Boot environment

rockchip: puma: fix GPT table corruption when saving U-Boot environment

The GPT table is taking the first 34 sectors, which amounts to 0x4400
bytes. Saving the environment below this address in storage will corrupt
the GPT table.

While technically the table ends at 0x4400, some tools (e.g. bmaptool)
are rounding everything to the logical block size (0x1000), so it is
safer to make it point to 0x5000 so that the environment could still
persist when flashing a sparse image with bmaptool or similar tools.

Obviously, the default 0x4000 environment size does not work anymore, so
let's set it to 0x3000 so it does fill the gap between the GPT table
(rounded to 0x1000) and the start of the idbloader.img.

Fixes: 56f580d3eb8d ("rockchip: dts: rk3399-puma: put environment (in MMC/SD configurations) before SPL")
Cc: Quentin Schulz <foss+uboot@0leil.net>
Signed-off-by: Quentin Schulz <quentin.schulz@theobroma-systems.com>
Reviewed-by: Kever Yang <kever.yang@rock-chips.com>