libmach: always print 0x on hex numbers

R=r
DELTA=3  (0 added, 0 deleted, 3 changed)
OCL=21558
CL=21558

src/libmach_amd64/8db.c

@@ -1931,7 +1931,7 @@ immediate(Instr *ip, vlong val)
 			w = -w;
 		if (issymref(ip, &s, w, val)) {
 			if (w)
-				bprint(ip, "%s+%lux(SB)", s.name, w);
+				bprint(ip, "%s+%#lux(SB)", s.name, w);
 			else
 				bprint(ip, "%s(SB)", s.name);
 			return;
@@ -1942,7 +1942,7 @@ immediate(Instr *ip, vlong val)
 			if (w < 0)
 				w = -w;
 			if (w < 4096) {
-				bprint(ip, "%s-%lux(SB)", s.name, w);
+				bprint(ip, "%s-%#lux(SB)", s.name, w);
 				return;
 			}
 		}

src/libmach_amd64/machdata.c

@@ -113,7 +113,7 @@ symoff(char *buf, int n, uvlong v, int space)
 	if (s.type != 't' && s.type != 'T' && delta >= 4096)
 		return snprint(buf, n, "%llux", v);
 	else if (delta)
-		return snprint(buf, n, "%s+%lux", s.name, delta);
+		return snprint(buf, n, "%s+%#lux", s.name, delta);
 	else
 		return snprint(buf, n, "%s", s.name);
 }