arm64, bpf: Use bpf_prog_pack for arm64 bpf trampoline

We used bpf_prog_pack to aggregate bpf programs into huge page to
relieve the iTLB pressure on the system. This was merged for ARM64[1]
We can apply it to bpf trampoline as well. This would increase the
preformance of fentry and struct_ops programs.

[1] https://lore.kernel.org/bpf/20240228141824.119877-1-puranjay12@gmail.com/



Signed-off-by: Puranjay Mohan <puranjay12@gmail.com>
Reviewed-by: Pu Lehui <pulehui@huawei.com>
Message-ID: <20240304202803.31400-1-puranjay12@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>