Openocd: svf: Add ability to ignore svf_check_tdo errors

Openocd: svf: Add ability to ignore svf_check_tdo errors

Added Openocd commandline argument to ignore_error when the
read back TDO does not match to expected value specified with
TDO after masking with what is specified in MASK. This allows
to continue to play entire SVF file ignoring errors.
Error logs clearly show the failure reason and prints
read back TDO value.

Change-Id: I324f476fc16a003b35e6f2c5b63976431f49d54a
Signed-off-by: Kamal Dasu <kdasu.kdev@gmail.com>
Reviewed-on: http://openocd.zylin.com/2129
Tested-by: jenkins
Reviewed-by: Franck Jullien <franck.jullien@gmail.com>
Reviewed-by: Andreas Fritiofson <andreas.fritiofson@gmail.com>