Read the offset for the framebuffer index from the instruction stream
instead of using a literal constant, so the hook works for other games
using the same function but a different offset (e.g. Zero no Kiseki).
Also remove the memcpy() since the original function will do it anyway
(and may do it differently if other games call the function with
different arguments).
Merge pull request #6836 from achurch/master

Brandish hook: read framebuffer index offset from instruction stream, drop memcpy()