Fix typo in comment.

CONFIG_PRREMPT -> CONFIG_PREEMPT

Signed-off-by: Florian La Roche <Florian.LaRoche@googlemail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/init/main.c b/init/main.c
index b795aa3..a404936 100644
--- a/init/main.c
+++ b/init/main.c
@@ -423,7 +423,7 @@
 
 	/*
 	 * Enable might_sleep() and smp_processor_id() checks.
-	 * They cannot be enabled earlier because with CONFIG_PRREMPT=y
+	 * They cannot be enabled earlier because with CONFIG_PREEMPT=y
 	 * kernel_thread() would trigger might_sleep() splats. With
 	 * CONFIG_PREEMPT_VOLUNTARY=y the init task might have scheduled
 	 * already, but it's stuck on the kthreadd_done completion.