Initialize Cipher Suite Privilege Levels cfg file

IPMI Spec 13.17 provides a way to pick a "highest level matching
proposed algorithms" during RMCPP Open Session Request, and effective
privilege levels are decided taking Cipher Suite Privilege Levels into
account. This patch ships default Cipher Suite Privilege Levels file
from root filesystem. By default, admin privileges are
given to all Cipher Suites across all channels.

Tested:
1. By default, cs_privilege_levels.json is present in location
   /usr/share/ipmi-providers/
Provided support from below patch.
https://gerrit.openbmc-project.xyz/#/c/openbmc/meta-phosphor/+/28923/
2. File data is as expected and persistent across reboots.
3. Manually deleted the json file while phosphor-ipmi-host was running
and rebooted and the file was re-created.

Change-Id: I526b8708f63659210768c77e8e19fa5a76df1f0d
Signed-off-by: Sumanth Bhat <sumanth.bhat@linux.intel.com>
Signed-off-by: vijayabharathix shetty <vijayabharathix.shetty@intel.com>
diff --git a/user_channel/channel_layer.hpp b/user_channel/channel_layer.hpp
index eaf631c..0fefe2e 100644
--- a/user_channel/channel_layer.hpp
+++ b/user_channel/channel_layer.hpp
@@ -14,6 +14,7 @@
 // limitations under the License.
 */
 #pragma once
+#include <array>
 #include <ipmid/api.hpp>
 #include <string>
 
@@ -25,6 +26,11 @@
 static constexpr uint8_t invalidChannel = 0xff;
 
 /**
+ * @array of privilege levels
+ */
+extern const std::array<std::string, PRIVILEGE_OEM + 1> privList;
+
+/**
  * @enum IPMI return codes specific to channel (refer spec se 22.22 response
  * data)
  */