drm/nouveau/fb/ramnv50: Fix DDR2 reclocking on NV50 architectures
On my venerable Geforce 9600M GT (on-board card), I got the message 'fb: Could not calculate MR' when reclocking the card. This was due to a missing call to the 'nvkm_sddr2_calc' function when calculating the memory clock frequency.
With this change, I no longer have any errors when reclocking, the memory frequency is correctly calculated, and I have a performance gain of around 30% on glxgears, and my card remains stable when running under wine or retroarch.
Edited by Jonathan Fouquart