Use single direct ops for bpf trampolines
bpf-AT-vger.kernel.org, linux-kernel-AT-vger.kernel.org, linux-trace-kernel-AT-vger.kernel.org, linux-arm-kernel-AT-lists.infradead.org, Alexei Starovoitov <ast-AT-kernel.org>, Daniel Borkmann <daniel-AT-iogearbox.net>, Andrii Nakryiko <andrii-AT-kernel.org>, Menglong Dong <menglong8.dong-AT-gmail.com>, Song Liu <song-AT-kernel.org>