iio: trigger: iio-trig-bfin-timer: select missing dependency

This driver requires CONFIG_BFIN_GPTIMERS.
Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
Acked-by: Jonathan Cameron <jic23@cam.ac.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/staging/iio/trigger/Kconfig

@@ -31,6 +31,7 @@ config IIO_SYSFS_TRIGGER
 config IIO_BFIN_TMR_TRIGGER
 	tristate "Blackfin TIMER trigger"
 	depends on BLACKFIN
+	select BFIN_GPTIMERS
 	help
 	  Provides support for using a Blackfin timer as IIO triggers.
 	  If unsure, say N (but it's safe to say "Y").