Correct minor name inconsistencies in ES

[jphickey]

Is your feature request related to a problem? Please describe.
There are some remaining naming convention inconsistencies in ES. Notably:

1. CC definitions named _SYSLOG_CC should be _SYS_LOG_CC - because CamelCase version is SysLog, therefore it is two words, not one. Alternatively, CamelCase version could be Syslog, but that's probably a more significant change.
2. The recently-added Perf Log enum does not follow convention. Labels should be e.g. CFE_ES_PerfTrigger_START, not CFE_ES_PERF_TRIGGER_START.

These are all just simple search/replace fixes.

Describe the solution you'd like
Rename symbols

Additional context
This inconsistency causes name mismatches when using generated headers, as the generated headers follow the conventions strictly.

Requester Info
Joseph Hickey, Vantage Systems, Inc.