[plugins/dpdk] Support for CLIB_HAVE_64 (aarch64)
[plugins/dpdk] Support for CLIB_HAVE_64 (aarch64)

For platforms which do not support u8x32, such as aarch64,
add an alternative implementation of 'dpdk_buffer_init_from_template'.

Change-Id: Ia7e8d0a5985fa5925e063ed6e890208c73e39933
Signed-off-by: Christophe Fontaine <45e030f39bbb5d342ea1aaf7ae211d57367c2315@enea.com>

FDio/vpp,vpp-dev/vpp,FDio/vpp,FDio/vpp,vpp-dev/vpp,chrisy/vpp,chrisy/vpp,vpp-dev/vpp,chrisy/vpp,chrisy/vpp,FDio/vpp,chrisy/vpp,FDio/vpp,vpp-dev/vpp,chrisy/vpp,chrisy/vpp,vpp-dev/vpp,FDio/vpp,chrisy/vpp,vpp-dev/vpp,FDio/vpp,vpp-dev/vpp,FDio/vpp