spi: bcm53xx: Fix module dependency

config SPI_BCM53XX needs to depend on BCMA_POSSIBLE and select BCMA.
This fixes below build error:
ERROR: "bcma_driver_unregister" [drivers/spi/spi-bcm53xx.ko] undefined!
ERROR: "__bcma_driver_register" [drivers/spi/spi-bcm53xx.ko] undefined!
Signed-off-by: Axel Lin <axel.lin@ingics.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

drivers/spi/Kconfig

@@ -115,6 +115,8 @@ config SPI_AU1550
 config SPI_BCM53XX
 	tristate "Broadcom BCM53xx SPI controller"
 	depends on ARCH_BCM_5301X
+	depends on BCMA_POSSIBLE
+	select BCMA
 	help
           Enable support for the SPI controller on Broadcom BCM53xx ARM SoCs.