user_layer: Add get/set user payload access.

IPMI Spec reference: Section 24.6, 24.7.
Support is added to get/set user access details for the
unreserved, supported payload types defined by Spec.
SOL is the only unreserved, supported payload currently.
If support is needed for unreserved std/oem payload
types in future, they can be enabled with minor source code
changes to this implementation.

All payload types are packed in a JSON object
"payload_enabled" in ipmi_user.json file.

Tested-by:
1. For user 8 in channel 3, Enable SOL payload.

   // Command - (channel 3 is of LAN channel type)
   ipmitool  -I lanplus...raw 0x06 0x4C 3 0x8 0x02 0 0 0
   // Verify it with Get User Payload Access Command
   ipmitool  -I lanplus...raw 0x06 0x4D 3 8
   02 00 00 00 // Response

2. Disable SOL payload.

   // Command
   ipmitool  -I lanplus...raw 0x06 0x4C 3 0x48 0x02 0 0x00 0
   // Verify it with Get User Payload Access Command
   ipmitool  -I lanplus...raw 0x06 0x4D 3 8
   00 00 00 00 // Response

3. Enable unsupported payload stdPayload7.

   // Command
   ipmitool  -I lanplus...raw 0x06 0x4C 3 0x8 0x80 0 0 0
   Error: Invalid data field in request // Response

Change-Id: Idc57b04a747e55666407d928d8b2169223501e5b
Signed-off-by: Saravanan Palanisamy <saravanan.palanisamy@linux.intel.com>
diff --git a/host-ipmid-whitelist.conf b/host-ipmid-whitelist.conf
index 038db34..5397115 100644
--- a/host-ipmid-whitelist.conf
+++ b/host-ipmid-whitelist.conf
@@ -26,6 +26,7 @@
 0x06:0x36    //<App>:<Get BT Interface Capabilities>
 0x06:0x37    //<App>:<Get System GUID>
 0x06:0x42    //<App>:<Get Channel Info Command>
+0x06:0x4D    //<App>:<Get User Payload Access>
 0x06:0x4E    //<App>:<Get Channel Payload Support>
 0x06:0x4F    //<App>:<Get Channel Payload Version>
 0x06:0x54    //<App>:<Get Channel Cipher Suites>