[Clean] Remove unused function

[Clean] Remove unused function

remove unused function before adaption multioutput.

Main reason for the clean is that the functions are not used but
hard to maintain for the incoming change of adapting multi output

**Self evaluation:**
1. Build test: [X]Passed [ ]Failed [ ]Skipped
2. Run test: [X]Passed [ ]Failed [ ]Skipped

Signed-off-by: Jihoon Lee <jhoon.it.lee@samsung.com>