breakpoints: use 64-bit type for watchpoint mask and value

breakpoints: use 64-bit type for watchpoint mask and value

This patch changes data types of watchpoint value and mask to allow for
64-bit values match that some architectures (like RISCV) allow.

In addition this patch fixes the behavior of watchpoint command to
zero-out mask if only data value is provided.

Change-Id: I3c7ec1630f03ea9534ec34c0ebe99e08ea56e7f0
Signed-off-by: Parshintsev Anatoly <anatoly.parshintsev@syntacore.com>
Reviewed-on: https://review.openocd.org/c/openocd/+/7840
Reviewed-by: Antonio Borneo <borneo.antonio@gmail.com>
Reviewed-by: Marek Vrbka <marek.vrbka@codasip.com>
Tested-by: jenkins
Reviewed-by: Tomas Vanek <vanekt@fbl.cz>