pldm: Remove unnecessary type casting in logs

This commit removes the unnecessary type casting of values of the
journal logs based on supported types mentioned in LG2 documentation
[1].

Testing: Verified the debug traces to correct.

'''
For Instance:
Earlier -
error(”TYPE = {TYPE} “, “TYPE”, static_cast<unsigned>(PLDM_STATE_EFFECTER_PDR));
Journal trace -
May 27 08:16:51 p10bmc pldmd[931]: TYPE = 11

After Correction -
error(”TYPE = {TYPE}“, “TYPE”, PLDM_STATE_EFFECTER_PDR);
Journal trace -
May 27 08:16:51 p10bmc pldmd[931]: TYPE = Enum(11)
'''

[1]: https://github.com/openbmc/phosphor-logging/blob/master/docs/structured-logging.md#lg2



Change-Id: Ia649ecd4ecbb73c421f7844885f58a6835805719
Signed-off-by: Riya Dixit <riyadixitagra@gmail.com>