x86: Shrink the x86-64 cabac coeff_last tables

x86: Shrink the x86-64 cabac coeff_last tables

Use dword instead of qword entries. Cuts the size of the tables in half
which allows each table fit inside a single cache line.

When PIC is disabled dwords are enough to store absolute addresses.

When PIC is enabled we can store dword offsets relative to the start of
the table and simply add the address of the table to the offset in order
to calculate the full address. This approach also have the advantage of
eliminating a whole bunch of run-time .data relocations.