mtd: spinand: Fix incorrect parameters for on-die ECC

The new generic NAND ECC framework stores the configuration and
requirements in separate places since commit 93ef92f6

 ("mtd: nand: Use
the new generic ECC object"). In 5.10.x The SPI NAND layer still uses only
the requirements to track the ECC properties. This mismatch leads to
values of zero being used for ECC strength and step_size in the SPI NAND
layer wherever nanddev_get_ecc_conf() is used and therefore breaks the SPI
NAND on-die ECC support in 5.10.x.

By using nanddev_get_ecc_requirements() instead of nanddev_get_ecc_conf()
for SPI NAND, we make sure that the correct parameters for the detected
chip are used. In later versions (5.11.x) this is fixed anyway with the
implementation of the SPI NAND on-die ECC engine.

Cc: stable@vger.kernel.org # 5.10.x
Reported-by: voice INTER connect GmbH <developer@voiceinterconnect.de>
Signed-off-by: Frieder Schrempf <frieder.schrempf@kontron.de>
Acked-by: Miquel Raynal <miquel.raynal@bootlin.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>