tracing: Move the trace_seq_* functions into its own trace_seq.c file

The trace_seq_*() functions are a nice utility that allows users to manipulate
buffers with printf() like formats. It has its own trace_seq.h header in
include/linux and should be in its own file. Being tied with trace_output.c
is rather awkward.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>

diff --cc include/linux/trace_seq.h
Simple merge

diff --cc kernel/trace/Makefile
Simple merge

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

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