Changed multi-line C comments into another style.

The left side doesn't look unbalanced.

src/ar65/objfile.h

@@ -60,8 +60,8 @@ struct ObjData;
 
 void ObjReadData (FILE* F, struct ObjData* O);
 /* Read object file data from the given file. The function expects the Name
- * and Start fields to be valid. Header and basic data are read.
- */
+** and Start fields to be valid. Header and basic data are read.
+*/
 
 void ObjAdd (const char* Name);
 /* Add an object file to the library */