KVM: PPC: e500: Silence bogus GCC warning in tlb code

64-bit GCC 4.5.1 warns about an uninitialized variable which was guarded
by a flag. Initialize the variable to make it happy.
Signed-off-by: Mihai Caraman <mihai.caraman@freescale.com>
[agraf: reword comment]
Signed-off-by: Alexander Graf <agraf@suse.de>

arch/powerpc/kvm/e500_tlb.c

@@ -415,7 +415,8 @@ static inline void kvmppc_e500_shadow_map(struct kvmppc_vcpu_e500 *vcpu_e500,
 	struct tlbe_ref *ref)
 {
 	struct kvm_memory_slot *slot;
-	unsigned long pfn, hva;
+	unsigned long pfn = 0; /* silence GCC warning */
+	unsigned long hva;
 	int pfnmap = 0;
 	int tsize = BOOK3E_PAGESZ_4K;