Fix thetering on nvidia

Wow, I finally have Plasma 5.27 running well on Debian 12 on Nvidia GT710.
I changed the driver to nouveau. Plasma Wayland works on it, but the problem was that it worked terribly slowly on this driver, it froze, etc., sometimes even the mouse cursor slowed down.
It turned out that reclocking was enough
as root:
cat /sys/kernel/debug/dri/0/pstate

something like this is displayed:
07: core 405MHz memory 810MHz
0f: core 653-954 MHz memory 1800 MHz AC DC *
AC: core 953 MHz memory 1800 MHz

as you can see, state 0f has the highest core and memory clocks, so we set this state:
echo "0f" > /sys/kernel/debug/dri/0/pstate

and it's done, now it runs without any interruption and even 3D applications run as fast as on the nvidia driver