Add Unsafe.IsAddressLess/GreaterThanOrEqualTo methods

[stephentoub]

Fixes #88478

[ghost]

Note regarding the new-api-needs-documentation label:

This serves as a reminder for when your PR is modifying a ref *.cs file and adding/modifying public APIs, please make sure the API implementation in the src *.cs file is documented with triple slash comments, so the PR reviewers can sign off that change.

[vargaz]

The mono changes look ok.

[EgorBo]

JIT looks ok too, but VM seems to be missing changes in jitinterface.cpp e.g.

runtime/src/coreclr/vm/jitinterface.cpp

Lines 6972 to 6986 in c430570

	else if (tk == CoreLibBinder::GetMethod(METHOD__UNSAFE__BYREF_IS_ADDRESS_LESS_THAN)->GetMemberDef())
	{
	// Compare the two arguments
	static const BYTE ilcode[] =
	{
	CEE_LDARG_0,
	CEE_LDARG_1,
	CEE_PREFIX1, (CEE_CLT_UN & 0xFF),
	CEE_RET
	};
	setILIntrinsicMethodInfo(methInfo,const_cast<BYTE*>(ilcode),sizeof(ilcode), 2);
	return true;
	}

(LessThan) as an example.

Presumably, we don't have to implement them in R2R/CoreCLR with raw il code and leave only JIT version if we make them "must expand"/recursive? (but it's not related to your PR - we can do that sort of clean up separately if it's possible)

[ghost]

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Issue Details

---

Fixes #88478

Author:	stephentoub
Assignees:	stephentoub
Labels:	area-System.Runtime.CompilerServices, new-api-needs-documentation, needs-area-label
Milestone:	-

[stephentoub]

@vargaz, it looks like while OP_ICLE_UN and OP_ICGE_UN exist, OP_LCLE_UN and OP_LCGE_UN don't. What would you recommend as the right way to implement this? Remove these defines and update intrinsics.c with an implementation that emits e.g. a cgt and ceq for less than or equal?