add d0 to clobber list

BaS_gcc/sys/interrupts.c

@@ -679,7 +679,7 @@ uint32_t set_ipl(uint32_t ipl)
         "		lsr.l	#8,%[ret]\r\n"			/* shift them to position */
         : [ret] "=&d" (ret)		/* output */
         : [ipl] "d" (ipl)		/* input */
-        : "cc"	/* clobber */
+        : "d0", "cc"	/* clobber */
     );
 
     return ret;