drm/nouveau: fix reclocking on nv40

In commit 77145f1 was introduced
error which cause that reclocking on nv40 not working anymore.
There is missing assigment of return value from pll_calc to ret.

Signed-off-by: Pali Rohár <[email protected]>
Signed-off-by: Martin Peres <[email protected]>
Signed-off-by: Ben Skeggs <[email protected]>

drivers/gpu/drm/nouveau/nv40_pm.c

@@ -131,7 +131,7 @@ nv40_calc_pll(struct drm_device *dev, u32 reg, struct nvbios_pll *pll,
 	if (clk < pll->vco1.max_freq)
 		pll->vco2.max_freq = 0;
 
-	pclk->pll_calc(pclk, pll, clk, &coef);
+	ret = pclk->pll_calc(pclk, pll, clk, &coef);
 	if (ret == 0)
 		return -ERANGE;