Revert "[future] Use mid-tier regalloc for huge functions"

This reverts commit 40b062ce.

Reason for revert: Failing Fuzz tests on arm - https://ci.chromium.org/ui/p/v8/builders/ci/V8%20Linux%20-%20arm%20-%20sim%20-%20debug/27306/overview

Original change's description:
> [future] Use mid-tier regalloc for huge functions
>
> Stage the --turbo-use-mid-tier-regalloc-for-huge-functions behind
> --future.
>
> R=​thibaudm@chromium.org
>
> Bug: v8:12287, v8:12320
> Change-Id: I7145ca1b022bfdcb0b61d6666daf855f14cbc4ce
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3236547
> Reviewed-by: Thibaud Michaud <thibaudm@chromium.org>
> Commit-Queue: Clemens Backes <clemensb@chromium.org>
> Cr-Commit-Position: refs/heads/main@{#77549}

Bug: v8:12287, v8:12320
Change-Id: Id86e9c0d44e6a273abdeb384f722ff308c56e70f
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3245342
Auto-Submit: Maya Lekova <mslekova@chromium.org>
Commit-Queue: Rubber Stamper <rubber-stamper@appspot.gserviceaccount.com>
Bot-Commit: Rubber Stamper <rubber-stamper@appspot.gserviceaccount.com>
Owners-Override: Maya Lekova <mslekova@chromium.org>
Cr-Commit-Position: refs/heads/main@{#77553}

src/flags/flag-definitions.h

@@ -923,8 +923,8 @@ DEFINE_BOOL(turbo_compress_translation_arrays, false,
             "compress translation arrays (experimental)")
 DEFINE_BOOL(turbo_inline_js_wasm_calls, true, "inline JS->Wasm calls")
 DEFINE_BOOL(turbo_use_mid_tier_regalloc_for_huge_functions, false,
-            "fall back to the mid-tier register allocator for huge functions")
-DEFINE_WEAK_IMPLICATION(future, turbo_use_mid_tier_regalloc_for_huge_functions)
+            "fall back to the mid-tier register allocator for huge functions "
+            "(experimental)")
 DEFINE_BOOL(turbo_force_mid_tier_regalloc, false,
             "always use the mid-tier register allocator (for testing)")