Update service to remove /delete from url and to update swagger api annotations

components/device-mgt/org.wso2.carbon.device.mgt.api/src/main/java/org/wso2/carbon/device/mgt/jaxrs/service/api/admin/DeviceTypeManagementAdminService.java

@@ -594,7 +594,7 @@ public interface DeviceTypeManagementAdminService {
 
 
     @DELETE
-    @Path("/{deviceTypeName}/delete")
+    @Path("/{deviceTypeName}")
     @ApiOperation(
             httpMethod = "DELETE",
             value = "Delete device type.",
@@ -618,6 +618,9 @@ public interface DeviceTypeManagementAdminService {
                     code = 401,
                     message = "Unauthorized.\n The unauthorized access to the requested resource.",
                     response = ErrorResponse.class),
+            @ApiResponse(
+                    code = 404,
+                    message = "Not Found. \n Device type trying to delete does not exist"),
             @ApiResponse(
                     code = 406,
                     message = "Not Acceptable. \n The requested media type is not supported"),

components/device-mgt/org.wso2.carbon.device.mgt.api/src/main/java/org/wso2/carbon/device/mgt/jaxrs/service/impl/admin/DeviceTypeManagementAdminServiceImpl.java

@@ -320,7 +320,7 @@ public class DeviceTypeManagementAdminServiceImpl implements DeviceTypeManagemen
 
     @Override
     @DELETE
-    @Path("/{deviceTypeName}/delete")
+    @Path("/{deviceTypeName}")
     public Response deleteDeviceType(@PathParam("deviceTypeName") String deviceTypeName) {
         try {
             DeviceManagementProviderService deviceManagementProviderService =