Adding Aarch64 support, for Travis

[advancedwebdeveloper]

For supporting multi-arch cross-compilation.
But that is not solving my issues, for on-premise compilation (where host arch=guest arch, i.e. arm64)

[mrutkows]

Interestingly, we are already producing the arm64 convenience binaries (even before adding this to the bash script) run on every merged PR build (i.e., "latest")...
https://github.com/apache/openwhisk-wskdeploy/releases/tag/latest

[advancedwebdeveloper]

I can tell that both https://github.com/apache/openwhisk-wskdeploy/releases/download/latest/openwhisk_wskdeploy-latest-linux-arm.tgz and https://github.com/apache/openwhisk-wskdeploy/releases/download/latest/openwhisk_wskdeploy-latest-linux-arm64.tgz contain executables, which run on

lscpu

Architecture: aarch64
CPU op-mode(s): 32-bit, 64-bit
Byte Order: Little Endian
CPU(s): 32
On-line CPU(s) list: 0-31
Thread(s) per core: 1
Core(s) per socket: 32
Socket(s): 1
NUMA node(s): 1
Vendor ID: APM
Model: 2
Model name: X-Gene
Stepping: 0x3
CPU max MHz: 3300.0000
CPU min MHz: 363.9700
BogoMIPS: 90.00
L1d cache: 1 MiB
L1i cache: 1 MiB
L2 cache: 4 MiB
NUMA node0 CPU(s): 0-31
Vulnerability Itlb multihit: Not affected
Vulnerability L1tf: Not affected
Vulnerability Mds: Not affected
Vulnerability Meltdown: Mitigation; PTI
Vulnerability Spec store bypass: Vulnerable
Vulnerability Spectre v1: Mitigation; __user pointer sanitization
Vulnerability Spectre v2: Vulnerable
Vulnerability Srbds: Not affected
Vulnerability Tsx async abort: Not affected
Flags: fp asimd evtstrm aes pmull sha1 sha2 crc32 cpuid

[mrutkows]

That indicates an Applied Micro chip from 2011... and whose X-Gene3 line was discontinued in 2016. Worldwide they only shipped 25,000 units across the 3 generations. No wonder it is reporting an older/outmoded architecture code. with "Core(s) per socket: 32" what manufacturer/model machine is this?