Only define fdt_pic_table on arm, and when not using intrng as this is

the only place that uses it.

sys/dev/fdt/fdt_common.h

@@ -45,8 +45,10 @@ struct fdt_sense_level {
 	enum intr_polarity	pol;
 };
 
+#if defined(__arm__) && !defined(ARM_INTRNG)
 typedef int (*fdt_pic_decode_t)(phandle_t, pcell_t *, int *, int *, int *);
 extern fdt_pic_decode_t fdt_pic_table[];
+#endif
 
 #if defined(__arm__) || defined(__powerpc__)
 typedef void (*fdt_fixup_t)(phandle_t);