selftests/sgx: Add test for TCS page permission changes

mainline inclusion
from mainline-6.0-rc1
commit 7088c81f
category: feature
bugzilla: https://gitee.com/openeuler/intel-kernel/issues/I5USAM


CVE: NA

Intel-SIG: commit 7088c81f selftests/sgx: Add test for TCS page
permission changes.
Backport for SGX EDMM support.

--------------------------------

Kernel should not allow permission changes on TCS pages. Add test to
confirm this behavior.

Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Acked-by: Jarkko Sakkinen <jarkko@kernel.org>
Link: https://lkml.kernel.org/r/0121ad1b21befb94519072e2c18b89aa5dca00d4.1652137848.git.reinette.chatre@intel.com


Signed-off-by: Zhiquan Li <zhiquan1.li@intel.com>