This refactors the debug side table such that we can easily add
register information later.
In particular
- vectors for types and stack offsets are combined into one;
- constants are stored in the same vector;
- locals and operand stack values are stored in the same vector.

A follow-up CL will extend the DebugSideTable to also encode locals
or operand stack values held in registers.

R=thibaudm@chromium.org

Bug: v8:10147, v8:10222
Change-Id: I97adb56b31afdb22896530c7ba2e8a24b5d31da9
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2062405
Commit-Queue: Clemens Backes <clemensb@chromium.org>
Reviewed-by: Thibaud Michaud <thibaudm@chromium.org>
Cr-Commit-Position: refs/heads/master@{#66374}