xfs: remove xfs_setattr_time() declaration

commit b0463b9d upstream.

xfs_setattr_time() has been removed since
commit e014f37d ("xfs: use setattr_copy to set vfs inode
attributes"), so remove it.

Signed-off-by: Gaosheng Cui <cuigaosheng1@huawei.com>
Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>