doc: add SVF optional arguments descriptions

Change-Id: I1a3e5b04b6bc4821c4d11c8fcb33b426d6d41bfb
Signed-off-by: Paul Fertser <fercerpav@gmail.com>
Reviewed-on: http://openocd.zylin.com/4314
Tested-by: jenkins
Reviewed-by: Jim Norris <u17263@att.net>
Reviewed-by: Karl Palsson <karlp@tweak.net.au>

doc/openocd.texi

@@ -8779,11 +8779,27 @@ way to represent JTAG test patterns in text files.
 In a debug session using JTAG for its transport protocol,
 OpenOCD supports running such test files.
 
-@deffn Command {svf} filename [@option{quiet}]
+@deffn Command {svf} @file{filename} [@option{-tap @var{tapname}}] [@option{[-]quiet}] @
+                     [@option{[-]nil}] [@option{[-]progress}] [@option{[-]ignore_error}]
 This issues a JTAG reset (Test-Logic-Reset) and then
 runs the SVF script from @file{filename}.
-Unless the @option{quiet} option is specified,
-each command is logged before it is executed.
+
+Arguments can be specified in any order; the optional dash doesn't
+affect their semantics.
+
+Command options:
+@itemize @minus
+@item @option{-tap @var{tapname}} ignore IR and DR headers and footers
+specified by the SVF file with HIR, TIR, HDR and TDR commands;
+instead, calculate them automatically according to the current JTAG
+chain configuration, targetting @var{tapname};
+@item @option{[-]quiet} do not log every command before execution;
+@item @option{[-]nil} ``dry run'', i.e., do not perform any operations
+on the real interface;
+@item @option{[-]progress} enable progress indication;
+@item @option{[-]ignore_error} continue execution despite TDO check
+errors.
+@end itemize
 @end deffn
 
 @section XSVF: Xilinx Serial Vector Format