EncoderFix-NonCTC: Error assigning RPL index in low delay configuration

Fix the encoder for selecting RPL idx when the max distance between current pic and ref pic never be greater than GOP size

The master crashed for the example below (LDP). Encoding/decoding works well with the fix.

#        Type POC QPoffset QPOffsetModelOff QPOffsetModelScale CbQPoffset CrQPoffset QPfactor tcOffsetDiv2 betaOffsetDiv2 CbTcOffsetDiv2 CbBetaOffsetDiv2 CrTcOffsetDiv2 CrBetaOffsetDiv2 temporal_id #ref_pics_active_L0 #ref_pics_L0   reference_pictures_L0 #ref_pics_active_L1 #ref_pics_L1   reference_pictures_L1
Frame1:    P   1   5       -6.5                      0.2590         0          0          1.0      0            0               0             0                 0               0               0             4                4         1 3 5 7                    0                   0
Frame2:    P   2   4       -6.5                      0.2590         0          0          1.0      0            0               0             0                 0               0               0             4                4         2 4 6 8                    0                   0
Frame3:    P   3   5       -6.5                      0.2590         0          0          1.0      0            0               0             0                 0               0               0             4                4         1 3 5 7                    0                   0
Frame4:    P   4   4       -6.5                      0.2590         0          0          1.0      0            0               0             0                 0               0               0             4                4         2 4 6 8                    0                   0
Frame5:    P   5   5       -6.5                      0.2590         0          0          1.0      0            0               0             0                 0               0               0             4                4         1 3 5 7                    0                   0
Frame6:    P   6   4       -6.5                      0.2590         0          0          1.0      0            0               0             0                 0               0               0             4                4         2 4 6 8                    0                   0
Frame7:    P   7   5       -6.5                      0.2590         0          0          1.0      0            0               0             0                 0               0               0             4                4         1 3 5 7                    0                   0
Frame8:    P   8   1        0.0                      0.0            0          0          1.0      0            0               0             0                 0               0               0             4                4         2 4 6 8                    0                   0

merged

mentioned in commit 1d53da88