splice: fix misleading comment
splice: fix misleading comment

Splice is tied to pipes by design, it'll not change. And now that
the splice stuff is in splice.h (and note pipe.h), the rest of the comment
is out-of-date as well.

Signed-off-by: Jens Axboe <165ab144a3ccfd9429d5c6466b275f24fafdb114@oracle.com>

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