mtd: spi-nor: spansion: Make RD_ANY_REG_OP macro take number of dummy bytes

Currently Read Any Register op is used to read volatile registers without
any dummy cycles, but the op requires dummy cycles depending on register
type (volatiler or non-volatile), device family, and device configuration.
Add 'ndummy' argument to RD_ANY_REG_OP macro to support other use cases.

Suggested-by: Tudor Ambarus <tudor.ambarus@linaro.org>
Signed-off-by: Takahiro Kuwano <Takahiro.Kuwano@infineon.com>
Link: https://lore.kernel.org/r/03756e9e3ac41d2016a71d2afb702398dd0b19ed.1677557525.git.Takahiro.Kuwano@infineon.com
Signed-off-by: Tudor Ambarus <tudor.ambarus@linaro.org>