Remove #define KERNEL.

cpukit/libnetworking/rtems/rtems_dhcp.c

@@ -61,10 +61,6 @@
  *   the end of the file should be removed
  */
 
-#ifndef KERNEL
-#define KERNEL
-#endif
-
 #ifndef __INSIDE_RTEMS_BSD_TCPIP_STACK__
 #define __INSIDE_RTEMS_BSD_TCPIP_STACK__
 #endif
@@ -1216,5 +1212,3 @@ rtems_bsdnet_do_dhcp_refresh_only (unsigned long xid,
 
   dhcp_start_task (sdl, &reply, 150);
 }
-
-#undef KERNEL