Fix potentially wrong code by dropping attributes after RecordDecls

[giulianobelinassi]

Previously, clang-extract dropped attribute(()) after the definition of a RecordDecl. This could possibly generate wrong code if the attribute is relevant for code layout, for example.

@marcosps Please check if it fixes the wrong code on TOMOYO.

Closes #13

[marcosps]

The attribute is now copied correctly:

/** clang-extract: from include/linux/sched.h:413:1  */                                                                             
struct sched_avg {                                                                                                                  
        u64                             last_update_time;                                                                           
        u64                             load_sum;                                                                                   
        u64                             runnable_sum;                                                                               
        u32                             util_sum;                                                                                   
        u32                             period_contrib;                                                                             
        unsigned long                   load_avg;                                                                                   
        unsigned long                   runnable_avg;                                                                               
        unsigned long                   util_avg;                                                                                   
        struct util_est                 util_est;                                                                                   
} ____cacheline_aligned;    

Thanks for fixing it!