[Review] Rename cache directory from comgr_cache to comgr

The cache is anyways under the default cache directory "$XDG_CACHE_HOME"

Author: jmmartinez

amd/comgr/README.md

@@ -126,8 +126,8 @@ By default, the cache is turned off, set the environment variable
 * `AMD_COMGR_CACHE`: When unset or set to 0, the cache is turned off.
 * `AMD_COMGR_CACHE_DIR`: When set to "", the cache is turned off. If assigned a
   value, that value is used as the path for cache storage. By default, it is
-  directed to "$XDG_CACHE_HOME/comgr_cache" (which defaults to
-  "$USER/.cache/comgr_cache" on Linux, and "%LOCALAPPDATA%\cache\comgr_cache"
+  directed to "$XDG_CACHE_HOME/comgr" (which defaults to
+  "$USER/.cache/comgr" on Linux, and "%LOCALAPPDATA%\cache\comgr"
   on Microsoft Windows).
 * `AMD_COMGR_CACHE_POLICY`: If assigned a value, the string is interpreted and
   applied to the cache pruning policy. The cache is pruned only upon program

amd/comgr/src/comgr-env.cpp

@@ -98,7 +98,7 @@ StringRef getCacheDirectory() {
     return Result;
 
   if (sys::path::cache_directory(Result)) {
-    sys::path::append(Result, Twine("comgr_cache"));
+    sys::path::append(Result, "comgr");
     return Result;
   }