mtd: rawnand: denali: Do not reset the block before booting the kernel

The Denali NAND driver in mainline Linux currently cannot deassert the
reset. The upcoming Linux 5.6 will support the reset controlling, and
also set up SPARE_AREA_SKIP_BYTES correctly. So, the Denali driver in
the future kernel will work without relying on any bootloader or firmware.
However, we still need to take care of stable kernel versions for a while.
U-boot should not assert the reset of this controller.

Fixes: ed784ac3 ("mtd: rawnand: denali: add reset handling")
Signed-off-by: Marek Vasut <marex@denx.de>
[yamada.masahiro: reword the commit description]
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>