tracing: disable tracepoints by default

while it's arguably low overhead, we dont enable new features by default.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/init/Kconfig b/init/Kconfig
index 7008267..d599449 100644
--- a/init/Kconfig
+++ b/init/Kconfig
@@ -773,7 +773,6 @@
 
 config TRACEPOINTS
 	bool "Activate tracepoints"
-	default y
 	help
 	  Place an empty function call at each tracepoint site. Can be
 	  dynamically changed for a probe function.