ratelimit: Drop redundant accesses to burst

Now that there is the "burst <= 0" fastpath, for all later code, burst
must be strictly greater than zero.  Therefore, drop the redundant checks
of this local variable.

Link: https://lore.kernel.org/all/fbe93a52-365e-47fe-93a4-44a44547d601@paulmck-laptop/
Link: https://lore.kernel.org/all/20250423115409.3425-1-spasswolf@web.de/
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Kuniyuki Iwashima <kuniyu@amazon.com>
Cc: Mateusz Guzik <mjguzik@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: John Ogness <john.ogness@linutronix.de>
Cc: Sergey Senozhatsky <senozhatsky@chromium.org>

Author: paulmckrcu

lib/ratelimit.c

@@ -58,7 +58,7 @@ int ___ratelimit(struct ratelimit_state *rs, const char *func)
 	 * the current lock owner is just about to reset it.
 	 */
 	if (!raw_spin_trylock_irqsave(&rs->lock, flags)) {
-		if (READ_ONCE(rs->flags) & RATELIMIT_INITIALIZED && burst &&
+		if (READ_ONCE(rs->flags) & RATELIMIT_INITIALIZED &&
 		    atomic_read(&rs->rs_n_left) > 0 && atomic_dec_return(&rs->rs_n_left) >= 0)
 			ret = 1;
 		goto nolock_ret;
@@ -90,7 +90,7 @@ int ___ratelimit(struct ratelimit_state *rs, const char *func)
 	}
 
 	/* Note that the burst might be taken by a parallel call. */
-	if (burst && atomic_read(&rs->rs_n_left) > 0 && atomic_dec_return(&rs->rs_n_left) >= 0)
+	if (atomic_read(&rs->rs_n_left) > 0 && atomic_dec_return(&rs->rs_n_left) >= 0)
 		ret = 1;
 
 unlock_ret: