mfd: atmel-smc: Add missing colon(s) for 'conf' arguments

Kerneldoc valication gets confused if syntax isn't "@.*: ".

Adding the missing colons squashes the following W=1 warnings:

drivers/mfd/atmel-smc.c:247: warning: Function parameter or member 'conf' not described in 'atmel_smc_cs_conf_apply'
drivers/mfd/atmel-smc.c:268: warning: Function parameter or member 'conf' not described in 'atmel_hsmc_cs_conf_apply'

Cc: Nicolas Ferre <nicolas.ferre@microchip.com>
Cc: Alexandre Belloni <alexandre.belloni@bootlin.com>
Cc: Ludovic Desroches <ludovic.desroches@microchip.com>
Cc: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

drivers/mfd/atmel-smc.c

@@ -237,7 +237,7 @@ EXPORT_SYMBOL_GPL(atmel_smc_cs_conf_set_cycle);
  * atmel_smc_cs_conf_apply - apply an SMC CS conf
  * @regmap: the SMC regmap
  * @cs: the CS id
- * @conf the SMC CS conf to apply
+ * @conf: the SMC CS conf to apply
  *
  * Applies an SMC CS configuration.
  * Only valid on at91sam9/avr32 SoCs.
@@ -257,7 +257,7 @@ EXPORT_SYMBOL_GPL(atmel_smc_cs_conf_apply);
  * @regmap: the HSMC regmap
  * @cs: the CS id
  * @layout: the layout of registers
- * @conf the SMC CS conf to apply
+ * @conf: the SMC CS conf to apply
  *
  * Applies an SMC CS configuration.
  * Only valid on post-sama5 SoCs.