LoongArch: BPF: Fix memory leak in bpf_jit_free()

In the Linux kernel, the following vulnerability has been resolved:

LoongArch: BPF: Fix memory leak in bpf_jit_free()

When bpf_int_jit_compile() is called for subprograms, it returns early
during the first pass (!prog->is_func || extra_pass is false), keeping
ctx->offset alive for the subsequent extra pass.

If JIT compilation fails for a later subprogram, the BPF core aborts and
calls bpf_jit_free() to clean up the first subprogram. However,
bpf_jit_free() fails to free jit_data->ctx.offset, which causes a memory
leak of the JIT context offsets array.

So fix this by adding the missing kvfree(jit_data->ctx.offset) in
bpf_jit_free().