libraw1394 struct layouts, i386 vs. x86_64

[Michael ODonnell]

>> Googling "gcc pragma pack" yielded the following link which seems
>> to explain it fairly well.
>>
>> http://gcc.gnu.org/onlinedocs/gcc/Structure_002dPacking-Pragmas.html
>
>
>Ha!  I was reading that very section in a freshly downloaded PDF

Dang - it looks like those pragma directives are for solving what
is basically the opposite problem; it seems that they can only
be used to force tighter packing while my situation calls for
my structure members to essentially be packed "less tightly" and
those pragmas appear to have no effect...   >-/