trace-cmd: Fix processing of dereferenced args in bprintk events

In the case that a bprintk event has a dereferenced pointer that is stored
as a string, and there's more values to process (more args), the arg was not
updated to point to the next arg after processing the dereferenced pointer,
and it screwed up what was to be displayed.

Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
diff --git a/lib/traceevent/event-parse.c b/lib/traceevent/event-parse.c
index 7980fc6..beca36f 100644
--- a/lib/traceevent/event-parse.c
+++ b/lib/traceevent/event-parse.c
@@ -4969,6 +4969,7 @@
 
 				if (arg->type == TEP_PRINT_BSTRING) {
 					trace_seq_puts(s, arg->string.string);
+					arg = arg->next;
 					break;
 				}