spi: microchip-core-qspi: remove unused param from mchp_coreqspi_write_op()

"word" is unused in mchp_coreqspi_write_op(), so delete it.

Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://patch.msgid.link/20250620-starry-excusably-25e6be957d9d@spud


Signed-off-by: Mark Brown <broonie@kernel.org>