Add infomation of test VMLAUNCH

Arthur
Add VMRESUME test cases, refine vmresume call path

The previous version can only imply the success of VMRESUME if no
FATAL error occurs when VMRESUME. This version add formal test
cases with VMRESUME, including passing %rax from hypervisor and
%rsp tests before VMCALL and after VMRESUME.

Refine VMRESUME call path. Now some debug info can be printed when
vmresume fails.

Arthur