Removed obsolete #if config from cc2530dk's main

Unlike cc2430, the cc2530 RF driver never generates interrupts.
This configuration in main() was a remnant of the porting from
the sensinode main, which does in fact need it.
Also updated comments in contiki-conf to reflect that shortcuts
don't influence the RF

platform/cc2530dk/contiki-conf.h

@@ -64,10 +64,6 @@
 
 /* Code Shortcuts */
 /*
- * When set, the RF driver is no longer a contiki process and the RX ISR is
- * disabled. Instead of polling the radio process when data arrives, we
- * periodically check for data by directly invoking the driver from main()
-
  * When set, this directive also configures the following bypasses:
  *   - process_post_synch() in tcpip_input() (we call packet_input())
  *   - process_post_synch() in tcpip_uipcall (we call the relevant pthread)

platform/cc2530dk/contiki-main.c

@@ -254,7 +254,6 @@ main(void)
       watchdog_periodic();
       r = process_run();
     } while(r > 0);
-#if SHORTCUTS_CONF_NETSTACK
     len = NETSTACK_RADIO.pending_packet();
     if(len) {
       packetbuf_clear();
@@ -264,7 +263,6 @@ main(void)
         NETSTACK_RDC.input();
       }
     }
-#endif
 
 #if LPM_MODE
 #if (LPM_MODE==LPM_MODE_PM2)