Ubuntu 18.04 support added to README

Signed-off-by: Ayoun Serge <[email protected]>

Author: sergeay

README.md

@@ -44,6 +44,8 @@ Build and Install the Intel(R) SGX Driver
 - Ensure that you have the following required operating systems:  
   * Ubuntu* 16.04.3 LTS Desktop 64bits
   * Ubuntu* 16.04.3 LTS Server 64bits
+  * Ubuntu* 18.04 LTS Desktop 64bits
+  * Ubuntu* 18.04 LTS Server 64bits
   * Red Hat Enterprise Linux Server release 7.4 64bits
   * Red Hat Enterprise Linux Server release 8.0 64bits
   * CentOS 7.4.1708 64bits