Intel EPT: Fix out of range right shift on 32-bit host

Intel EPT: Fix out of range right shift on 32-bit host

Currently, there has a logic to check whether the EPT GFN is exceeding
guest physical address width. It uses right shift(>>) to implement the
check. But the right shift count is greater than the width of the
type(unsigned long = 32) under the PAE. And this will cause guest boot
fail under PAE with EPT supported.

Signed-off-by: Li Xin <xin.li@intel.com>
Signed-off-by: Zhang Yang <yang.z.zhang@intel.com>