ftrace: clean up of using ftrace_event_enable_disable()
ftrace: clean up of using ftrace_event_enable_disable()

Always use ftrace_event_enable_disable() to enable/disable an event
so that we can factorize out the event toggling code.

[ Impact: factorize and cleanup event tracing code ]

Signed-off-by: Zhao Lei <aacdd228f50c574b28b524b23f12fb9d52d6e0e3@cn.fujitsu.com>
Cc: Steven Rostedt <43232e92d70cc7aa53504ad0397085ee47bad87f@goodmis.org>
Cc: Tom Zanussi <ca42f6846873622f2a6dc51a5106ba83ffbdaf95@gmail.com>
LKML-Reference: <c28eaec2c399636a857816469fed8bf35e0bdf14@cn.fujitsu.com>
Signed-off-by: Frederic Weisbecker <e8a1bf9163cb25e93cfd6540f223b3872ea7ee55@gmail.com>

KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas