sunxi_nand_spl: Drop unnecessary temp buf

sunxi_nand_spl: Drop unnecessary temp buf

nand_spl_load_image() always gets called with either CONFIG_SYS_TEXT_BASE
or spl_image.load_addr as destination, both of which are properly aligened,
and have plenty of space for "overshooting" up to
CONFIG_NAND_SUNXI_SPL_ECC_PAGE_SIZE bytes, as we read in
CONFIG_NAND_SUNXI_SPL_ECC_PAGE_SIZE bytes chunks.

This saves CONFIG_NAND_SUNXI_SPL_ECC_PAGE_SIZE (typically 1k) in
SPL size, which is a lot on the total 24k we have.

Note this changes the dma destination from SRAM to DRAM, so this patch
updates the DDMA_DST_TYPE bits in the dma controller cfg0 reg accordingly.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Acked-by: Ian Campbell <ijc@hellion.org.uk>