bpf: Take return from set_memory_rox() into account with bpf_jit_binary_lock_ro()

In the Linux kernel, the following vulnerability has been resolved: bpf: Take return from set_memory_rox() into account with bpf_jit_binary_lock_ro() set_memory_rox() can fail, leaving memory unprotected. Check return and bail out when bpf_jit_binary_lock_ro() returns an error.