compilation fail for 256 UE

The root cause is the static (global) variable total size is limited to a 32bit offset in Linux exe format (elf format).

OAI uses a lot of global/static very big variables, so the total size of the oai binary file offsets for global variables is above the maximum.

The largest static variable in OAI is: mem_block_var (300MB), so we will move it to the heap.

On longer term, we must revise the OAI code that do max size allocations, such as MAX_UEMAX_ARQ... and use a smarter memory management