SWDEV-461599 - scrub HCC in hip documents (#178)

CONTRIBUTING.md

@@ -52,7 +52,7 @@ For applications and benchmarks outside the hip-tests environment, developments
   * Tabs should be expanded to spaces.
   * Use 4 spaces indentation.
 * Capitalization and Naming
-  * Prefer camelCase for HIP interfaces and internal symbols.  Note HCC uses _ for separator.
+  * Prefer camelCase for HIP interfaces and internal symbols.  Note `HIP_CLANG` uses `_` for separator.
     This guideline is not yet consistently followed in HIP code * eventual compliance is aspirational.
   * Member variables should begin with a leading "_".  This allows them to be easily distinguished from other variables or functions.