Added s390x support

Signed-off-by: vitthalb@us.ibm.com <vitthalb@us.ibm.com>

scripts/get-helm-3

@@ -33,6 +33,7 @@ initArch() {
     x86_64) ARCH="amd64";;
     i686) ARCH="386";;
     i386) ARCH="386";;
+    s390x) ARCH="s390x";;
   esac
 }
 
@@ -60,7 +61,7 @@ runAsRoot() {
 # verifySupported checks that the os/arch combination is supported for
 # binary builds.
 verifySupported() {
-  local supported="darwin-386\ndarwin-amd64\nlinux-386\nlinux-amd64\nlinux-arm\nlinux-arm64\nlinux-ppc64le\nwindows-386\nwindows-amd64"
+  local supported="darwin-386\ndarwin-amd64\nlinux-386\nlinux-amd64\nlinux-arm\nlinux-arm64\nlinux-ppc64le\nlinux-s390x\nwindows-386\nwindows-amd64"
   if ! echo "${supported}" | grep -q "${OS}-${ARCH}"; then
     echo "No prebuilt binary for ${OS}-${ARCH}."
     echo "To build from source, go to https://github.com/helm/helm"