random: make it possible to enable debugging without rebuild

The module parameter that turns debugging mode (which basically means
printing a few extra lines during runtime) is in '#if 0' block. Forcing
everyone who would like to see how entropy is behaving on his system to
rebuild seems to be a little bit too harsh.

If we were concerned about speed, we could potentially turn 'debug' into a
static key, but I don't think it's necessary.

Drop the '#if 0' block to allow using the 'debug' parameter without rebuilding.

Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

drivers/char/random.c

@@ -399,7 +399,6 @@ static DECLARE_WAIT_QUEUE_HEAD(random_read_wait);
 static DECLARE_WAIT_QUEUE_HEAD(random_write_wait);
 static struct fasync_struct *fasync;
 
-#if 0
 static bool debug;
 module_param(debug, bool, 0644);
 #define DEBUG_ENT(fmt, arg...) do { \
@@ -410,9 +409,6 @@ module_param(debug, bool, 0644);
 		blocking_pool.entropy_count,\
 		nonblocking_pool.entropy_count,\
 		## arg); } while (0)
-#else
-#define DEBUG_ENT(fmt, arg...) do {} while (0)
-#endif
 
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