bcc/tools: Replace bpf_probe_read with bpf_probe_read_kernel

It is recommended to use bpf_probe_read_kernel_{str} in the bpf tools.
See kernel commit 0ebeea8ca8a4 ("bpf: Restrict bpf_probe_read{, str}()
only to archs where they work")

Signed-off-by: Sumanth Korikkar <sumanthk@linux.ibm.com>
Acked-by: Ilya Leoshkevich <iii@linux.ibm.com>
diff --git a/tools/dbslower.py b/tools/dbslower.py
index ffbb5e1..9db225f 100755
--- a/tools/dbslower.py
+++ b/tools/dbslower.py
@@ -158,8 +158,8 @@
         data.timestamp = tempp->timestamp;
         data.duration = delta;
 #if defined(MYSQL56) || defined(MYSQL57)
-	// We already copied string to the bpf stack. Hence use bpf_probe_read()
-        bpf_probe_read(&data.query, sizeof(data.query), tempp->query);
+	// We already copied string to the bpf stack. Hence use bpf_probe_read_kernel()
+        bpf_probe_read_kernel(&data.query, sizeof(data.query), tempp->query);
 #else
 	// USDT - we didnt copy string to the bpf stack before.
         bpf_probe_read_user(&data.query, sizeof(data.query), tempp->query);