tracing: Fix event format export

For some reason the export of the event print format to userspace
uses '#fmt' which breaks if the format string is anything but a plain
string, for example if it is built with macros then the macro names
are exported instead of their contents.

Use
	"\"%s\"", fmt
instead of
	"%s", #fmt
to export the string and not the way it is built.

For example, in net/mac80211/driver-trace.h for the trace event drv_start
there is:

        TP_printk(
                LOCAL_PR_FMT, LOCAL_PR_ARG
        )

Which use to produce:

 print fmt: LOCAL_PR_FMT, REC->wiphy_name

Now produces:

 print fmt: "%s", REC->wiphy_name

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
LKML-Reference: <20091113224009.GB23942@elte.hu>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>