qcacmn: Use ENABLE_DP_HIST_STATS to enable histogram functions

At present, DP_STATS_XXX and DP_HIST_XXX can be disabled
or enabled at the same time using macro DISABLE_DP_STATS.
Make DP_STATS_XXX and DP_HIST_XXX under different macro
so that both can be enabled/disabled separately.

HIST_STATS are by default disabled and can be enabled by
enabling ENABLE_DP_HIST_STATS macro.

Change-Id: I4e7b817afef040407a496e268f2fd680791fc47b
CRs-fixed: 2449710
1 file changed