net: Description of net_pkt_skip() is not clear

[pfalcon]

Current docstring of net_pkt_skip() (as introduced in b039625) reads:

 * @brief Skip some data from a net_pkt
 *
 * Note: net_pkt's cursor should be properly initialized
 *       Cursor will be updated according to parameter.
 *       Depending on the value of pkt->overwrite bit, this function
 *       will affect the buffer length or not: if it's 0, skip will
 *       actually apply the move in the buffer as it had written in it.

Specifically, the behavior re: pkt->overwrite isn't very clear. Neither "if it's 0" part is clear. For me it reads as: "If overwrite set to false, actually overwrite something in the packet". Can it be reworded to avoid such interpretations? Or perhaps, we really have an API clarity issue here? Maybe the function should be renamed, e.g. to net_pkt_seek() (but the question rises re: backward seeks).