spi: s3c24xx: correct kerneldoc comment

Correct the kerneldoc for structure to fix W=1 compile warning:

    drivers/spi/spi-s3c24xx.c:36: warning: cannot understand function prototype: 'struct s3c24xx_spi_devstate '
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Acked-by: Andi Shyti <andi@etezian.org>
Link: https://lore.kernel.org/r/20200804151356.28057-1-krzk@kernel.orgSigned-off-by: Mark Brown <broonie@kernel.org>

drivers/spi/spi-s3c24xx.c

@@ -28,7 +28,7 @@
 #include "spi-s3c24xx-fiq.h"
 
 /**
- * s3c24xx_spi_devstate - per device data
+ * struct s3c24xx_spi_devstate - per device data
  * @hz: Last frequency calculated for @sppre field.
  * @mode: Last mode setting for the @spcon field.
  * @spcon: Value to write to the SPCON register.