correct a bug caused by using.texi, a not interpreted comment @c/*...

docs/texinfo/chapters/using.texi

@@ -782,7 +782,7 @@ int MORSE_Desc_Getoncpu(MORSE_desc_t  *desc);
 @node Options routines
 @subsubsection Options routines
 
-@c/* Options */ 
+@c /* Options */ 
 Enable MORSE feature.
 @verbatim
 int MORSE_Enable  (MORSE_enum option);
@@ -1378,4 +1378,4 @@ int MORSE_zunmqr_Tile_Async(MORSE_enum side, MORSE_enum trans,
 
 @end verbatim
 
-@c -nofor_main
\ No newline at end of file
+@c -nofor_main