HIP Fixes

[ajaypanyala]

HIP: implement missing Fxc/vxc_fxc device stubs and complete builtin functional coverage

The HIP backend (unlike CUDA and SYCL) never implemented Fxc/vxc_fxc (second XC derivative) device evaluation, and separately, builtin.hip's explicit template instantiation list only covered 28 of the 102 functional types CUDA's builtin.cu instantiates. Both left vtable symbols unresolved at link time for any executable that actually links (as opposed to just archiving) against libexchcxx built for HIP -- e.g. ordinary SVWN5/M06-2X calculations, or anything touching Fxc contraction.

• hip/builtin.hip: add generic (KernelType-templated) stub definitions for the LDA/GGA/MGGA device_eval_{fxc,vxc_fxc}[_inc]helper* function templates, throwing std::runtime_error at call time. Wire them into the {LDA,GGA,MGGA}_GENERATE_DEVICE_HELPERS macros so every instantiated functional type gets them. Also complete the type list itself: append the 74 functional types (mostly GGA/meta-GGA -- PBE, M06 family, TPSS, SCAN-adjacent, etc.) present in cuda/builtin.cu but missing here entirely, so their ordinary EXC/VXC evaluation -- which the shared kernel_traits math already supports -- actually gets compiled for HIP.
• hip/libxc_device.hip: add the missing LibxcKernelImpl eval_fxc_device_/eval_vxc_fxc_device_ (and inc variants) overrides using the existing UNUSED_DEVICE_(INC_)INTERFACE_GENERATOR macros -- the same idiom already used here for eval_*inc_device and in builtin_kernel.cxx for disabled kernels.
• hip/xc_functional_device.hip: stub XCFunctional::eval_fxc_device/ eval_vxc_fxc_device (LDA/GGA/MGGA) the same way; these aggregate over each constituent kernel's (now-stubbed) eval_*_fxc_device.