Import phosphor-logging header files from new directory

Phase2: Changing the phosphor-logging header files import from
base dir to files under phosphor-logging folder. Once all projects
import from the new dir, the files in the base dir will be deleted.

Change-Id: I7152da5f0737171b9919bd082b09aa8ce4761430
Signed-off-by: Saqib Khan <khansa@us.ibm.com>
4 files changed