Add linux trace events

Add the output of the linux trace buffer to user dumps, with
lowest priority since the file can be large (~10MB).

Change-Id: I186b123154098400245f24db438e2a79a8da8b10
Signed-off-by: Eddie James <eajames@linux.ibm.com>
diff --git a/ffdc b/ffdc
index f08649a..5587a33 100644
--- a/ffdc
+++ b/ffdc
@@ -30,6 +30,7 @@
       "BMC_dmesg.txt"             "dmesg"
       "BMC_procinfo.txt"          "cat /proc/cpuinfo"
       "BMC_meminfo.txt"           "cat /proc/meminfo"
+      "BMC_traceevents.txt"       "cat /sys/kernel/tracing/trace"
 
 # Copy all content from these directories into directories in the .tar
 # Format: "Directory name" "Directory to copy"