nvme-trace: do not export nvme_trace_disk_name

nvme_trace_disk_name() is now already being invoked with the function
prototype in trace.h.  We don't need to export this symbol at all.

The following patches are going to provide target-side trace feature
with the exactly same function with this so that this patch removes the
EXPORT_SYMBOL() for this function.

Signed-off-by: Minwoo Im <minwoo.im.dev@gmail.com>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

drivers/nvme/host/trace.c

@@ -145,6 +145,5 @@ const char *nvme_trace_disk_name(struct trace_seq *p, char *name)
 
 	return ret;
 }
-EXPORT_SYMBOL_GPL(nvme_trace_disk_name);
 
 EXPORT_TRACEPOINT_SYMBOL_GPL(nvme_sq);