Fix missing std:: prefix for PROFILE_OPTIMIZER_STEPS

[cameel]

Looks like the profiling we have for optimizer steps in Suite.cpp broke with the removalof using namespace std. This is a trivial fix to add the std:: prefix.

Note that we never build in CI with -DPROFILE_OPTIMIZER_STEPS, so CI will pass here regardless of whether it's broken or not.

[cameel]

The reason why I noticed it in the first place is that I wanted to see what is taking the most time in the optimizer now, especially on full projects. I think we only ever ran it on single contracts.

Here's what I got. This is on top of #15451, which is what we'll release as 0.8.28 soon.

Note that these are cumulative results over all contracts in a project. Normally the profiler prints the results separately for each contract, but I made m_durationPerStepInMicroseconds static in my local build to get cumulative results.

OpenZeppelin

Time (relative)	Time (absolute)	Step
20%	3.7 s	CommonSubexpressionEliminator
9%	1.7 s	UnusedAssignEliminator
9%	1.6 s	UnusedPruner
9%	1.6 s	ExpressionSimplifier
7%	1.3 s	LiteralRematerialiser
7%	1.3 s	FullInliner
5%	1.0 s	ConditionalUnsimplifier
5%	0.9 s	LoadResolver
5%	0.9 s	DeadCodeEliminator
5%	0.8 s	SSATransform
4%	0.7 s	UnusedStoreEliminator
4%	0.7 s	ConditionalSimplifier
3%	0.6 s	LoopInvariantCodeMotion
2%	0.4 s	FunctionSpecializer
1%	0.2 s	EqualStoreEliminator
1%	0.2 s	ExpressionSplitter

Uniswap

Time (relative)	Time (absolute)	Step
20%	12.3 s	CommonSubexpressionEliminator
9%	5.8 s	ExpressionSimplifier
9%	5.3 s	UnusedAssignEliminator
8%	5.1 s	UnusedPruner
8%	5.1 s	LiteralRematerialiser
7%	4.2 s	FullInliner
5%	3.0 s	SSATransform
5%	3.0 s	ConditionalUnsimplifier
4%	2.7 s	DeadCodeEliminator
4%	2.7 s	LoadResolver
4%	2.4 s	UnusedStoreEliminator
4%	2.3 s	ConditionalSimplifier
3%	1.8 s	FunctionSpecializer
3%	1.7 s	LoopInvariantCodeMotion
1%	0.6 s	ExpressionSplitter

Eigenlayer

Time (absolute)	Time (relative)	Step
20%	52.3 s	CommonSubexpressionEliminator
11%	29.2 s	LiteralRematerialiser
9%	24.1 s	ExpressionSimplifier
9%	23.6 s	UnusedAssignEliminator
8%	20.5 s	FullInliner
7%	18.4 s	UnusedPruner
5%	13.7 s	LoadResolver
5%	13.3 s	SSATransform
4%	11.7 s	UnusedStoreEliminator
4%	11.2 s	ConditionalUnsimplifier
4%	10.3 s	DeadCodeEliminator
3%	8.1 s	ConditionalSimplifier
3%	7.3 s	LoopInvariantCodeMotion
2%	3.9 s	FunctionSpecializer

Comparison

Step	OpenZeppelin	Uniswap	Eigenlayer
CommonSubexpressionEliminator	20%	20%	20%
LiteralRematerialiser	7%	8%	11%
UnusedAssignEliminator	9%	9%	9%
ExpressionSimplifier	9%	9%	9%
FullInliner	7%	7%	8%
UnusedPruner	9%	8%	7%
LoadResolver	5%	4%	5%
SSATransform	5%	5%	5%
ConditionalUnsimplifier	5%	5%	4%
DeadCodeEliminator	5%	4%	4%
UnusedStoreEliminator	4%	4%	4%
ConditionalSimplifier	4%	4%	3%
LoopInvariantCodeMotion	3%	3%	3%
FunctionSpecializer	2%	3%	2%
EqualStoreEliminator	1%
ExpressionSplitter	1%	1%