wifi: libertas: Follow renaming of SPI "master" to "controller"

In commit 8caab75f ("spi: Generalize SPI "master" to "controller"")
some functions and struct members were renamed. To not break all drivers
compatibility macros were provided.

To be able to remove these compatibility macros push the renaming into
this driver.
Acked-by: Kalle Valo <kvalo@kernel.org>
Acked-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/971429eacddbad4c2f49b783ddd68746c1929ab3.1707324794.git.u.kleine-koenig@pengutronix.deSigned-off-by: Mark Brown <broonie@kernel.org>

drivers/net/wireless/marvell/libertas/if_spi.c

@@ -1052,7 +1052,7 @@ static int if_spi_init_card(struct if_spi_card *card)
 				"attached to SPI bus_num %d, chip_select %d. "
 				"spi->max_speed_hz=%d\n",
 				card->card_id, card->card_rev,
-				card->spi->master->bus_num,
+				card->spi->controller->bus_num,
 				spi_get_chipselect(card->spi, 0),
 				card->spi->max_speed_hz);
 		err = if_spi_prog_helper_firmware(card, helper);