powerpc/kvm: no need to check return value of debugfs_create functions

When calling debugfs functions, there is no need to ever check the
return value.  The function can work or not, but the code logic should
never do something different based on this.

Because of this cleanup, we get to remove a few fields in struct
kvm_arch that are now unused.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[mpe: Fix build error in kvm/timing.c, adapt kvmppc_remove_cpu_debugfs()]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200209105901.1620958-2-gregkh@linuxfoundation.org
diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c
index 2cefd07..33be4d9 100644
--- a/arch/powerpc/kvm/book3s_hv.c
+++ b/arch/powerpc/kvm/book3s_hv.c
@@ -2258,14 +2258,9 @@ static void debugfs_vcpu_init(struct kvm_vcpu *vcpu, unsigned int id)
 	struct kvm *kvm = vcpu->kvm;
 
 	snprintf(buf, sizeof(buf), "vcpu%u", id);
-	if (IS_ERR_OR_NULL(kvm->arch.debugfs_dir))
-		return;
 	vcpu->arch.debugfs_dir = debugfs_create_dir(buf, kvm->arch.debugfs_dir);
-	if (IS_ERR_OR_NULL(vcpu->arch.debugfs_dir))
-		return;
-	vcpu->arch.debugfs_timings =
-		debugfs_create_file("timings", 0444, vcpu->arch.debugfs_dir,
-				    vcpu, &debugfs_timings_ops);
+	debugfs_create_file("timings", 0444, vcpu->arch.debugfs_dir, vcpu,
+			    &debugfs_timings_ops);
 }
 
 #else /* CONFIG_KVM_BOOK3S_HV_EXIT_TIMING */