Syntax: added '.hh' and '.hpp' file extensions as C++ sources

'.hh' are used in projects, such as blackbox
'.hpp' are quite popular everywhere

Signed-off-by: Sergei Trofimovich <st@anti-virus.by>

syntax/Syntax

@@ -85,7 +85,7 @@ include texinfo.syntax
 file ..\*\\.c$ C\sProgram
 include c.syntax
 
-file ..\*\\.([hC]|CC|cxx|cc|cpp|CPP|CXX|hxx|h\.in)$ C/C\+\+\sProgram
+file ..\*\\.([hC]|CC|cxx|cc|cpp|CPP|CXX|hxx|hh|hpp|h\.in)$ C/C\+\+\sProgram
 include cxx.syntax
 
 file ..\*\\.d$ D\sProgram