Use constants for PortMapping log messages Step 4

Use constants for PortMapping log messages Step 4

Few PortMapping log messages were redundant and needed to be realigned.
They were fixed previously but this created new string for the words
"create" and "update" and "found".
Sonar complains they are used multiples times.
Since these words are shared among all PortMappingVersion*** classes,
migrating them to constants in the PortMappingUtils class is preferable.

JIRA: TRNSPRTPCE-355 TRNSPRTPCE-356
Signed-off-by: guillaume.lambert <guillaume.lambert@orange.com>
Change-Id: I71a5e8eb654256004f11d10e9f3d3273d79bcede