drm/i915/hdcp: check streams[] bounds before overflow

In the Linux kernel, the following vulnerability has been resolved: drm/i915/hdcp: check streams[] bounds before overflow The data->streams[] overflow check is done after the buffer overflow has already happened. Move the overflow check before the write. Side note, emitting a warning splat with a backtrace might be overkill here, but prefer not changing the behaviour other than not doing the overrun. Discovered using AI-assisted static analysis confirmed by Intel Product Security. (cherry picked from commit 9284ab3b6e776c315883ac2611283d263c9460fd)