Increase min-max q range for normal inter frames.

Allow the encode loop to select from a wider range of Q values
when encoding normal (non arf or kf) frames.

This change is targeted at improving psycho-visual quality in some
easy sections that are currently not getting enough bits.
This is likely to be a little worse from a metrics perspective  and may also
have a small impact on encode speed in cases where extra recode
iterations are triggered.

Change-Id: I667eebf33c753bcbcf8b93596467369e5708b889

vp9/encoder/vp9_ratectrl.c

@@ -133,7 +133,7 @@ static void init_minq_luts(int *kf_low_m, int *kf_high_m,
     kf_high_m[i] = get_minq_index(maxq, 0.0000021, -0.00125, 0.55, bit_depth);
     arfgf_low[i] = get_minq_index(maxq, 0.0000015, -0.0009, 0.30, bit_depth);
     arfgf_high[i] = get_minq_index(maxq, 0.0000021, -0.00125, 0.55, bit_depth);
-    inter[i] = get_minq_index(maxq, 0.00000271, -0.00113, 0.90, bit_depth);
+    inter[i] = get_minq_index(maxq, 0.00000271, -0.00113, 0.70, bit_depth);
     rtc[i] = get_minq_index(maxq, 0.00000271, -0.00113, 0.70, bit_depth);
   }
 }