[SPIRV] OpAccessChain storage class mismatch when accessing resource member in struct array

[bob80905]

When compiling HLSL that creates an array of structs with resource members and accesses them via constant indexing, DXC's SPIRV backend generates invalid SPIR-V:

fatal error: generated SPIR-V is invalid: The result pointer storage class and base pointer storage class in OpAccessChain do not match. %13 = OpAccessChain %_ptr_Uniform_uint %gBuf %uint_0 %uint_0

Repro:

RWByteAddressBuffer gBuf : register(u0);

struct BufStruct { RWByteAddressBuffer buf; };

[numthreads(1,1,1)] 
void main() {  
BufStruct s[2];  
s[0].buf = gBuf;
s[0].buf.Store(0, 42); 
}

Command:

dxc.exe -spirv -fspv-target-env=vulkan1.3 -T cs_6_0 -Fo out.spv repro.hlsl

DXC DXIL compiles and runs this correctly. DXC version: main (built from source).