trace: Remove "info trace" from documents

commit 88affa1c monitor: remove unused do_info_trace

has removed "info trace" function from monitor, so remove it from documents.
Signed-off-by: NLiming Wang <walimisdev@gmail.com>
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>

docs/tracing.txt

@@ -189,15 +189,6 @@ records the char* pointer value instead of the string that is pointed to.
 
 ==== Monitor commands ====
 
-* info trace
-  Display the contents of trace buffer.  This command dumps the trace buffer
-  with simple formatting.  For full pretty-printing, use the simpletrace.py
-  script on a binary trace file.
-
-  The trace buffer is written into until full.  The full trace buffer is
-  flushed and emptied.  This means the 'info trace' will display few or no
-  entries if the buffer has just been flushed.
-
 * trace-file on|off|flush|set <path>
   Enable/disable/flush the trace file or set the trace file name.
 

hmp-commands.hx

@@ -1573,13 +1573,6 @@ show roms
 @end table
 ETEXI
 
-#ifdef CONFIG_TRACE_SIMPLE
-STEXI
-@item info trace
-show contents of trace buffer
-ETEXI
-#endif
-
 STEXI
 @item info trace-events
 show available trace events and their state