hw/ppc/spapr: Restrict part of PAGE_INIT hypercall to TCG

Restrict the tb_flush() call to TCG. Assert we are using KVM or TCG.

Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Harsh Prateek Bora <harshpb@linux.ibm.com>
Message-Id: <20250127102620.39159-3-philmd@linaro.org>

hw/ppc/spapr_hcall.c

@@ -299,8 +299,10 @@ static target_ulong h_page_init(PowerPCCPU *cpu, SpaprMachineState *spapr,
     if (flags & (H_ICACHE_SYNCHRONIZE | H_ICACHE_INVALIDATE)) {
         if (kvm_enabled()) {
             kvmppc_icbi_range(cpu, pdst, len);
-        } else {
+        } else if (tcg_enabled()) {
             tb_flush(CPU(cpu));
+        } else {
+            g_assert_not_reached();
         }
     }