Add support for ATSAMG55x19 Rev.B.
Both chips have nearly the same cidr, however, Rev.B has an incremented version.
Change-Id: I5939c41fa5d54c4d3bfb850964974b878f709d13
Signed-off-by: Benedikt-Alexander Mokroß <mokross@gessler.de>
Reviewed-on: http://openocd.zylin.com/5825
Reviewed-by: Tomas Vanek <vanekt@fbl.cz>
Tested-by: jenkins