examples/tracing: Use printb to improve python3 compatibility

When using python3, 'print' will output the bytes arrays with the "b"
prefix. Switch to printb to get rid of the prefix.

Signed-off-by: Gary Lin <glin@suse.com>
diff --git a/examples/tracing/tcpv4connect.py b/examples/tracing/tcpv4connect.py
index 8a89469..81385e8 100755
--- a/examples/tracing/tcpv4connect.py
+++ b/examples/tracing/tcpv4connect.py
@@ -16,6 +16,7 @@
 
 from __future__ import print_function
 from bcc import BPF
+from bcc.utils import printb
 
 # define BPF program
 bpf_text = """
@@ -76,11 +77,11 @@
     "DPORT"))
 
 def inet_ntoa(addr):
-	dq = ''
+	dq = b''
 	for i in range(0, 4):
-		dq = dq + str(addr & 0xff)
+		dq = dq + str(addr & 0xff).encode()
 		if (i != 3):
-			dq = dq + '.'
+			dq = dq + b'.'
 		addr = addr >> 8
 	return dq
 
@@ -89,7 +90,7 @@
 	# Read messages from kernel pipe
 	try:
 	    (task, pid, cpu, flags, ts, msg) = b.trace_fields()
-	    (_tag, saddr_hs, daddr_hs, dport_s) = msg.split(" ")
+	    (_tag, saddr_hs, daddr_hs, dport_s) = msg.split(b" ")
 	except ValueError:
 	    # Ignore messages from other tracers
 	    continue
@@ -98,7 +99,7 @@
 	if _tag != "trace_tcp4connect":
 	    continue
 
-	print("%-6d %-12.12s %-16s %-16s %-4s" % (pid, task,
+	printb(b"%-6d %-12.12s %-16s %-16s %-4s" % (pid, task,
 	    inet_ntoa(int(saddr_hs, 16)),
 	    inet_ntoa(int(daddr_hs, 16)),
 	    dport_s))