LU-5932 tests: load sunrpc module before insmod ptlrpc_gss

LU-5932 tests: load sunrpc module before insmod ptlrpc_gss

Lustre ptlrpc_gss module depends on Linux kernel sunrpc module.
This patch fixes load_module() in test-framework.sh to load the
sunrpc module before loading ptlrpc_gss module by using insmod.

Signed-off-by: Jian Yu <jian.yu@intel.com>
Change-Id: Idf22fa9023a2fada9038e16fbc3e8a61530266bc
Reviewed-on: http://review.whamcloud.com/12790
Tested-by: Jenkins
Tested-by: Maloo <hpdd-maloo@intel.com>
Reviewed-by: Bob Glossman <bob.glossman@intel.com>
Reviewed-by: Wei Liu <wei3.liu@intel.com>
Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>