added icrc checksum implementation from SKA and added testbench for rdma

applications/rdma_demo/hdllib.cfg

applications/rdma_demo/libraries/rdma_generator/hdllib.cfg

..._generator/src/vhdl/rdma_generator_eth_tester_wrapper.vhd

.../libraries/rdma_generator/src/vhdl/rdma_generator_pkg.vhd

...es/rdma_generator/src/vhdl/rdma_generator_roce_tester.vhd

...generator/src/vhdl/rdma_generator_roce_tester_wrapper.vhd

...mo/libraries/rdma_generator/tb/vhdl/tb_rdma_generator.vhd

applications/rdma_demo/libraries/rdma_icrc/hdllib.cfg

...ons/rdma_demo/libraries/rdma_icrc/src/vhdl/append_crc.vhd

...mo/libraries/rdma_icrc/src/vhdl/append_crc_dp_wrapper.vhd

..._demo/libraries/rdma_icrc/src/vhdl/append_crc_wrapper.vhd

...ibraries/rdma_icrc/src/vhdl/bit_width_config_pkg.512b.vhd

.../rdma_demo/libraries/rdma_icrc/src/vhdl/crc_generator.vhd

...tions/rdma_demo/libraries/rdma_icrc/src/vhdl/rdma_pkg.vhd

...dma_demo/libraries/rdma_icrc/src/vhdl/wk_lib/AXI4_pkg.vhd

...o/libraries/rdma_icrc/src/vhdl/wk_lib/PCK_CRC32_D1024.vhd

...mo/libraries/rdma_icrc/src/vhdl/wk_lib/PCK_CRC32_D128.vhd

...emo/libraries/rdma_icrc/src/vhdl/wk_lib/PCK_CRC32_D16.vhd

...aries/rdma_icrc/src/vhdl/wk_lib/PCK_CRC32_D1_reversed.vhd

...mo/libraries/rdma_icrc/src/vhdl/wk_lib/PCK_CRC32_D256.vhd