Add internal APIs for querying the reason for the current acquired focus(playback...

Add internal APIs for querying the reason for the current acquired focus(playback/recording) in the system

int sound_manager_get_reason_for_current_playback_focus(sound_stream_focus_change_reason_e *acquired_by, char **additional_info)
int sound_manager_get_reason_for_current_recording_focus(sound_stream_focus_change_reason_e *acquired_by, char **additional_info)
User can get the reason for the current acquired focus via the new APIs globally.
Modify debug logs.

[Version] Release 0.3.37
[profile] Common
[Issue Type] Feature enhancement

Change-Id: If635cfe476376f6a69d88ffec9d46fb0616c6490
Signed-off-by: Sangchul Lee <sc11.lee@samsung.com>