log, refactor: use guard clause in LogCategoriesList()

and minor formatting fixups

src/logging.cpp

@@ -126,8 +126,7 @@ bool BCLog::Logger::DefaultShrinkDebugFile() const
     return m_categories == BCLog::NONE;
 }
 
-struct CLogCategoryDesc
-{
+struct CLogCategoryDesc {
     BCLog::LogFlags flag;
     std::string category;
 };
@@ -188,13 +187,11 @@ std::vector<LogCategory> BCLog::Logger::LogCategoriesList() const
 
     std::vector<LogCategory> ret;
     for (const CLogCategoryDesc& category_desc : categories) {
-        // Omit the special cases.
-        if (category_desc.flag != BCLog::NONE && category_desc.flag != BCLog::ALL) {
-            LogCategory catActive;
-            catActive.category = category_desc.category;
-            catActive.active = WillLogCategory(category_desc.flag);
-            ret.push_back(catActive);
-        }
+        if (category_desc.flag == BCLog::NONE || category_desc.flag == BCLog::ALL) continue;
+        LogCategory catActive;
+        catActive.category = category_desc.category;
+        catActive.active = WillLogCategory(category_desc.flag);
+        ret.push_back(catActive);
     }
     return ret;
 }
@@ -244,7 +241,7 @@ namespace BCLog {
         }
         return ret;
     }
-}
+} // namespace BCLog
 
 void BCLog::Logger::LogPrintStr(const std::string& str, const std::string& logging_function, const std::string& source_file, const int source_line)
 {