The RZ/{G2L,G2LC,V2L} SMARC EVK uses Micron MT25QU412A flash and RZ/G2UL
SMARC EVK uses Renesas AT25QL128A flash. With current pin setting for
IOVF pin, 4-bit flash write fails for AT25QL128A flash. Use Hi-Z state
as the default for IOVF pin, so that spi controller driver in linux will
be independent of flash type.

To support this, during board production, the bit 4 of the NV config
register must be cleared by the bootloader for Micron flash.

Output from u-boot after clearing bit4 of NVCR register.
=> renesas_micron_flash_nvcr
SF: Detected mt25qu512a with page size 256 Bytes, erase size 64 KiB, total 64 MiB
NVCR=0xef
Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
Link: https://lore.kernel.org/r/20240830203014.199326-2-biju.das.jz@bp.renesas.comSigned-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>