bpf, riscv: add fsession support for trampolines

bpf, riscv: add fsession support for trampolines

Implement BPF_TRACE_FSESSION support in the RISC-V trampoline JIT. The
logic here is similar to what we did in x86_64.

In order to simply the logic, we factor out the function invoke_bpf() for
fentry and fexit.

Signed-off-by: Menglong Dong <dongml2@chinatelecom.cn>
Tested-by: Björn Töpel <bjorn@kernel.org>
Acked-by: Björn Töpel <bjorn@kernel.org>
Link: https://lore.kernel.org/r/20260208053311.698352-3-dongml2@chinatelecom.cn
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Reviewed-by: Pu Lehui <pulehui@huawei.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>