kconfig: use bool instead of boolean for type definition attributes

Support for keyword 'boolean' will be dropped later on.

No functional change.

Reference: http://lkml.kernel.org/r/cover.1418003065.git.cj@linux.com
Signed-off-by: Christoph Jaeger <cj@linux.com>
Signed-off-by: Michal Marek <mmarek@suse.cz>
diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig
index 6529c09..33149a4 100644
--- a/drivers/hwmon/Kconfig
+++ b/drivers/hwmon/Kconfig
@@ -1595,7 +1595,7 @@
 	  will be called w83795.
 
 config SENSORS_W83795_FANCTRL
-	boolean "Include automatic fan control support (DANGEROUS)"
+	bool "Include automatic fan control support (DANGEROUS)"
 	depends on SENSORS_W83795
 	default n
 	help