update-test-path: Fix architecture in PATH

update-test-path

 PATH=${TESTPATH}/common:${TESTPATH}/bin:$PATH
 TESTPATH=$(pwd)
 case `uname -m` in
-x86_64) PATH=${TESTPATH}/bin/amd64:$PATH; ;;
-armv7l) PATH=${TESTPATH}/bin/armhf:$PATH; ;;
-aarch64) PATH=${TESTPATH}/bin/:$PATH; ;;
+x86_64) PATH=${TESTPATH}/amd64/bin:$PATH; ;;
+armv7l) PATH=${TESTPATH}/armhf/bin:$PATH; ;;
+aarch64) PATH=${TESTPATH}/arm64/bin:$PATH; ;;
 esac