remove bit_size & bit_offset from struct access_data
In struct access_data, the fields: 'bit_offset', 'bit_size'
are always the ones corresponding to the 'result_type' and
are thus completely redundant.
Change this by removing these fields and directly using
the info from the 'result_type' field.
Note: the motivation for this change is the realization that the
initialization of bitfields are buggy because 'bit_size'
is never set for initializers. The bug could be solved by
initializing 'bit_size' & 'bit_offset' but it is much
simpler (and feel safer) to simply use the values from
'result_type'.
Signed-off-by: Luc Van Oostenryck <luc.vanoostenryck@gmail.com>