tracing: clean up splice code
tracing: clean up splice code

Ingo Molnar suggested a series of clean ups for the splice code.
This patch implements those suggestions.

Signed-off-by: Steven Rostedt <9d183ff83abfec5c556edaf86a280a53916a11d8@redhat.com>

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