Revert "[regalloc] temporarily disable control-flow aware allocation"

This reverts commit a3039123.

Reason for revert: https://crrev.com/c/1985990 should fix the root-cause now.

Original change's description:
> [regalloc] temporarily disable control-flow aware allocation
> 
> Bug: v8:10077
> 
> Change-Id: I4b76d62462658dfa54f351ba10e52e57f63f3493
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1977857
> Commit-Queue: Tobias Tebbi <tebbi@chromium.org>
> Reviewed-by: Thibaud Michaud <thibaudm@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#65536}

TBR=tebbi@chromium.org,thibaudm@chromium.org

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

Bug: v8:10077
Change-Id: I356f1cc8d70f1f9efdbc72e3398cc830c51b664d
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1986002Reviewed-by: Tobias Tebbi <tebbi@chromium.org>
Commit-Queue: Tobias Tebbi <tebbi@chromium.org>
Cr-Commit-Position: refs/heads/master@{#65608}

src/flags/flag-definitions.h

@@ -523,7 +523,7 @@ DEFINE_BOOL(print_deopt_stress, false, "print number of possible deopt points")
 DEFINE_BOOL(opt, true, "use adaptive optimizations")
 DEFINE_BOOL(turbo_sp_frame_access, false,
             "use stack pointer-relative access to frame wherever possible")
-DEFINE_BOOL(turbo_control_flow_aware_allocation, false,
+DEFINE_BOOL(turbo_control_flow_aware_allocation, true,
             "consider control flow while allocating registers")
 
 DEFINE_STRING(turbo_filter, "*", "optimization filter for TurboFan compiler")