Unit tests for:
aom_jnt_comp_avg_pred_c
aom_jnt_sadmxn_avg_c
aom_sadmxh_sse2
aom_jnt_comp_avg_pred_ssse3
aom_jnt_sadmxn_avg_ssse3

Change-Id: I22463f143fd6513fd68f4bb82203e1b4fe3bbab7