use REV on aarch64 for endianness swapping (VPP-1067)
use REV on aarch64 for endianness swapping (VPP-1067)

Change-Id: I2de52725f40380422ca5019405df36cc05681603
Signed-off-by: Gabriel Ganne <54ed6f2b99047a4f6b8431ec375373608f566aee@enea.com>

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