tcl/arc: Fix ARC v2 registers r22/r23

There was a typo in the register numbering.

Signed-off-by: Robert Kovacsics <kovirobi@gmail.com>
Change-Id: Ie5d306725962c42f1bce976b80968145e6d0a177
Reviewed-on: https://review.openocd.org/c/openocd/+/7860


Tested-by: jenkins
Reviewed-by: Oleksij Rempel <linux@rempel-privat.de>