tracing: make print_(b)printk_msg_only global

This patch makes print_printk_msg_only and print_bprintk_msg_only
global for other functions to use. It also renames them by adding
a "trace_" to the beginning to avoid namespace collisions.

Signed-off-by: Steven Rostedt <srostedt@redhat.com>

diff --cc kernel/trace/trace.c
Simple merge

diff --cc kernel/trace/trace_output.c
Simple merge

diff --cc kernel/trace/trace_output.h
Simple merge