fastpatch: use thread passed as parameter

[axel-h]

Use the thread passed as parameter instead of making assumption that this is in sync with the global state.

Using NODE_STATE(ksCurThread) feels semantically wrong when cur_thread is passed to the function. It seems this function is not supposed to ever be called with cur_thread being different to NODE_STATE(ksCurThread), so I wonder if an explicit assert in the code should be added then to state this (and catch potential copy/paste porting errors).