This is what the Unix/Oracle team did to make the connection (Thanks JK and TN). Hope this helps other folks.
- Install a ODBC driver manager. It looks like Oracle recommends unixODBC (http://www.unixodbc.org/)
- The SAP HANA client installed, which includes the ODBC driver for HANA
- The particular HANA instance setup as a data source in ODBC on the Linux box
- Install Oracle Database Gateway for ODBC (http://docs.oracle.com/cd/E16338_01/gateways.112/e12070/toc.htm)
- Configure the gateway to connect to the HANA instance (http://docs.oracle.com/cd/B28359_01/gateways.111/b31042/configodbc.htm), which includes setting up a new database link