Reserve enum range for internal MR180 (#575)

To be used for in-development KHR extension.

Author: Ewan Crawford

xml/cl.xml

@@ -585,7 +585,10 @@ server's OpenCL/api-docs repository.
             <unused start="-1126" end="-1137"/>
     </enums>
 
-    <enums start="-1138" end="-9999" name="ErrorCodes.future" vendor="Khronos" comment="RESERVED FOR FUTURE ALLOCATIONS BY KHRONOS">
+    <enums start="-1138" end="-1140" name="ErrorCodes.1138" vendor="Khronos" comment="Reserved for MR180">
+    </enums>
+
+    <enums start="-1141" end="-9999" name="ErrorCodes.future" vendor="Khronos" comment="RESERVED FOR FUTURE ALLOCATIONS BY KHRONOS">
             <unused start="-1138" end="-9999"/>
     </enums>
 
@@ -1527,7 +1530,8 @@ server's OpenCL/api-docs repository.
         <enum value="0x1284"        name="CL_PROFILING_COMMAND_COMPLETE"/>
             <unused start="0x1285" end="0x128F" comment="Reserved for cl_profiling_info"/>
             <unused start="0x1290" end="0x1292" comment="Reserved for MR179"/>
-            <unused start="0x1293" end="0x1FFF" comment="Reserved for core API tokens"/>
+            <unused start="0x1293" end="0x12AB" comment="Reserved for MR180"/>
+            <unused start="0x12AC" end="0x1FFF" comment="Reserved for core API tokens"/>
     </enums>
 
     <enums start="0x2000" end="0x201F" name="enums.2000" vendor="Khronos" comment="Reserved for interop with other APIs">