This reverts commit 5b744bfb.

Reason for revert: Breaks node.js install:
https://ci.chromium.org/p/v8/builders/luci.v8.ci/V8%20Linux64%20-%20node.js%20integration/1546

Original change's description:
> Fix and extend lldbinit
> 
> 1) Define all commands in one file.
> 2) Add logic to make 'jco' print current pc by default.
> 3) Add a comment to explain how to load the lldb_commands.py file.
> 4) Minor refactorings.
> 
> R=​ahaas@chromium.org
> No-Try: true
> 
> Bug: v8:7754
> Change-Id: I553f2ce4cefedad05466c692a8665a570372b76a
> Reviewed-on: https://chromium-review.googlesource.com/1127892
> Reviewed-by: Andreas Haas <ahaas@chromium.org>
> Commit-Queue: Clemens Hammacher <clemensh@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#54329}

TBR=ahaas@chromium.org,clemensh@chromium.org

# Not skipping CQ checks because original CL landed > 1 day ago.

Bug: v8:7754
Change-Id: Iecaaf53ce6536395f83a78046f0375ec77003356
Reviewed-on: https://chromium-review.googlesource.com/1132878Reviewed-by: Michael Achenbach <machenbach@chromium.org>
Reviewed-by: Yang Guo <yangguo@chromium.org>
Commit-Queue: Yang Guo <yangguo@chromium.org>
Cr-Commit-Position: refs/heads/master@{#54375}