NSH library: Allow USB trace without a USB console

arch/arm/src/sama5/chip/sam_pwm.h

@@ -46,6 +46,9 @@
 /************************************************************************************
  * Pre-processor Definitions
  ************************************************************************************/
+
+#define SAM_PWM_NCHANNELS          4      /* Four channels numbered 0..3 */
+
 /* PWM Register Offsets *************************************************************/
 
 #define SAM_PWM_CLK_OFFSET         0x0000 /* PWM Clock Register */

configs/spark/src/up_composite.c

@@ -310,7 +310,7 @@ static int do_composite_archinitialize(void)
 
 int composite_archinitialize(void)
 {
-#if defined(CONFIG_NSH_ARCHINIT)
+#if defined(CONFIG_NSH_ARCHINIT) && defined(CONFIG_NSH_BUILTIN_APPS)
   return OK;
 #else
   return do_composite_archinitialize();