Fix cpplint errors

Fixes errors from the following categories:

- `readability/inheritance`
- `readability/braces`
- `readability/multiline_comment`
- `whitespace/newline`
- `whitespace/empty_if_body`
- `build/include_what_you_use`
- `build/header_guard`

Author: vkucera

PWGHF/D2H/Macros/HFInvMassFitterLinkDef.h

@@ -18,14 +18,11 @@
 /// \author Biao Zhang <biao.zhang@cern.ch>
 /// \author Oleksii Lubynets <oleksii.lubynets@cern.ch>
 
-#ifndef PWGHF_D2H_MACROS_HFINVMASSFITTERLINKDEF_H_
-#define PWGHF_D2H_MACROS_HFINVMASSFITTERLINKDEF_H_
+// NOLINT(build/header_guard)
 
 #ifdef __CINT__
 #pragma link off all globals;
 #pragma link off all classes;
 #pragma link off all functions;
 #pragma link C++ class HFInvMassFitter + ;
 #endif
-
-#endif // PWGHF_D2H_MACROS_HFINVMASSFITTERLINKDEF_H_