[SPIR-V] DXC generates invalid SPIRV for multiple entry points

Description
DXC generates invalid SPIRV with following error

fatal error: generated SPIR-V is invalid: In Logical addressing, variables can only allocate a storage buffer pointer if the VariablePointersStorageBuffer capability is declared
%Foo = OpVariable %_ptr_Private__ptr_StorageBuffer_type_StructuredBuffer_v4float Private

Steps to Reproduce
https://godbolt.org/z/hhxdPoaGT

Options used : -spirv -T lib_6_6 -fspv-target-env=vulkan1.3
--->

Actual Behavior
The shader seems legal and generates DXIL

The issue seems to be spirv-opt PrivateToLocal will not handle cases like above post inlining with multiple entry points
If DXC adds "VariablePointersStorageBuffer" capability this should end up working

Erroring out such hard to support cases seems fine as well

Environment

• DXC version libdxcompiler.so: 1.10(dev;1-948629ac); libdxil.so: 1.10
• Host OS : Windows

Start with the Godbolt reproduction using -spirv -T lib_6_6 -fspv-target-env=vulkan1.3 and inspect the generated SPIR-V validation error. Investigate the described spirv-opt PrivateToLocal behavior after inlining with multiple entry points. Done means the legal shader produces valid SPIR-V, or the compiler reports a clear unsupported-case error.