Update common/buildcraft/transport/TileGenericPipe.java

the old loop was useless, simply stepping to the next block, then calling update on this.

"this" is flagged for a render update on exit from this function call in the main Update thread, so calling this.scheduleRenderUpdate() does nothing; this loop was probably intended to flag all neighbors for a render update after "this" changed state. (either that, or this loop can be removed).

given that bc works without graphical glitches at the moment, either there is excessive over-rendering elsewhere, or this loop can be completely removed.