Unskip sized deallocation tests with clang

[h-vetinari]

I saw the following

STL/tests/libcxx/expected_results.txt

Lines 360 to 365 in e36ee6c

	# *** CLANG ISSUES, NOT YET ANALYZED ***
	# Clang doesn't enable sized deallocation by default. Should we add -fsized-deallocation or do something else?
	std/language.support/support.dynamic/new.delete/new.delete.array/sized_delete_array_fsizeddeallocation.pass.cpp:2 SKIPPED
	std/language.support/support.dynamic/new.delete/new.delete.array/sized_delete_array14.pass.cpp:2 SKIPPED
	std/language.support/support.dynamic/new.delete/new.delete.single/sized_delete_fsizeddeallocation.pass.cpp:2 SKIPPED
	std/language.support/support.dynamic/new.delete/new.delete.single/sized_delete14.pass.cpp:2 SKIPPED

This must have narrowly missed the update in #4702, because clang now finally supports (since llvm/llvm-project@130e93c) sized allocation by default, see also here.

[frederick-vs-ja]

I'd like to add -fsized-deallocation at this moment and say TRANSITION, Clang 19, LLVM-90373.

[StephanTLavavej]

FYI, my PR #4713 updates LLVM sufficiently to pick up that commit.

[frederick-vs-ja]

This will be resolved by recent toolset update #5247.