avdevice/timefilter-test: dont try to optimize par1 for n0=0 case

for the n0=0 case there are multiple solutions and different
platforms pick different ones
This should reduce the issues with fate and the timefilter test
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

libavdevice/timefilter.c

@@ -118,7 +118,8 @@ int main(void)
                 double par0, par1;
                 better = 0;
                 for (par0 = bestpar0 * 0.8; par0 <= bestpar0 * 1.21; par0 += bestpar0 * 0.05) {
-                    for (par1 = bestpar1 * 0.8; par1 <= bestpar1 * 1.21; par1 += bestpar1 * 0.05) {
+                    double range = n0 ? 0.8 : 1.0;
+                    for (par1 = bestpar1 * range; par1 <= bestpar1 * (2.01 - range); par1 += bestpar1 * 0.05) {
                         double error   = 0;
                         TimeFilter *tf = ff_timefilter_new(1, par0, par1);
                         for (i = 0; i < SAMPLES; i++) {

tests/ref/fate/timefilter

- [   0.800000    0.800000  0.000000] [   0.800000 2758.779681  0.000000] [   0.800000 3881.880055  0.000000] [   0.800000 5213.913473  0.000000]
+ [   0.800000    1.000000  0.000000] [1689.810931    1.000000  0.000000] [2480.175715    1.000000  0.000000] [3323.672664    1.000000  0.000000]
  [1688.672234    0.000000  0.018551] [  21.026792    0.000401  0.068856] [   1.162481    0.008576  0.121287] [   0.803356    0.016078  0.153518]
  [1218.378235    0.000000  0.167011] [  12.908626    0.000281  0.296858] [  21.026792    0.000401  0.619608] [   2.064064    0.004760  1.020336]
  [1218.378235    0.000000  0.909282] [  10.047626    0.000191  0.873495] [  14.909464    0.000297  1.935407] [  21.026792    0.000401  3.373312]