Intel: Uniformscaling compilation error

After #285, `gpuarrays/uniformscaling` started to fail on Intel. The reduced SPIR-V:

```spirv
%u2 = OpTypeInt 2 0
%long = OpTypeInt 64 2
%long_1 = OpConstant %long 1
%4 = OpTypeFunction %long %long
%_struct_5 = OpTypeStruct
%_ptr_Function__struct_5 = OpTypePointer Function %_struct_5
%_struct_7 = OpTypeStruct
%_ptr_Function__struct_7 = OpTypePointer Function %_struct_7
%9 = OpTypeFunction %_ptr_Function__struct_5 %u2
%11 = OpFunction %10 None %4
%12 = OpFunctionParameter %long
%13 = OpLabel
%14 = OpIAddCarry %long %long_1 %12
OpBranch %15
OpUnreachable
%15 = OpLabel
%16 = OpFunction %10 None %9
%17 = OpFunctionParameter %_ptr_Function__struct_7
%18 = OpLabel
%20 = OpInBoundsPtrAccessChain %19 %17 %11
```

```
Build error at wip9.c:138:

error: undefined reference to `_Z17__spirv_IAddCarryll'
in function: '__spirv_IAddCarry(long, long)' called indirectly by at least one of the kernels.

error: backend compiler failed build.
```

Reproduce the Intel failure in gpuarrays/uniformscaling and inspect the reduced SPIR-V plus wip9.c around line 138. Trace the indirect __spirv_IAddCarry reference through the backend build; done means the Intel compilation completes without the reported undefined-reference error.

Written by the indexing model from the issue text.