fs: simplify do_splice_from

No need for a local function pointer when we can trivial branch on the
->splice_write presence.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This commit is contained in:
Christoph Hellwig 2020-05-20 17:58:11 +02:00 • committed by Al Viro
commit 00c285d0d0