bplist: Improve UINT_TO_HOST macro, remove uint24_from_be function
bplist: Improve UINT_TO_HOST macro, remove uint24_from_be function

The uint24_from_be function used memcpy and a call to byte_convert.
Instead the macro now shifts the data appropriately with a new beNtoh
macro that eventually uses be64toh.
This commit also fixes the problem where binary plist data with other
non-power-of-2 sizes (like 5,6, or 7) where not handled correctly,
and actually supports sizes larger than 8 bytes though only the last
8 bytes are actually converted (nobody will come up with such a large
plist anyway).

libimobiledevice-win32/libplist,libimobiledevice-win32/libplist,libimobiledevice-win32/libplist,libimobiledevice/libplist,Tatsh/libplist,libimobiledevice/libplist,Tatsh/libplist,libimobiledevice-win32/libplist,Tatsh/libplist,Tatsh/libplist,libimobiledevice/libplist