Fix MMIO support for VirtIO ACPI: virtio_acpi.c already depends on

virtio_mmio.c, it worked only by accident on Arm kernels which already had
virtio_mmio pulled in

Author: iMilnb

sys/dev/acpi/files.acpi

@@ -1,4 +1,4 @@
-#	$NetBSD: files.acpi,v 1.136 2024/12/30 12:31:10 jmcneill Exp $
+#	$NetBSD: files.acpi,v 1.137 2025/01/03 05:57:06 imil Exp $
 
 defflag	opt_acpi.h	ACPIVERBOSE ACPI_DEBUG ACPI_ACTIVATE_DEV
 			ACPI_DSDT_OVERRIDE ACPI_SCANPCI ACPI_BREAKPOINT
@@ -297,7 +297,7 @@ attach	amdccp at acpinodebus with amdccp_acpi
 file	dev/acpi/amdccp_acpi.c		amdccp_acpi
 
 # QEMU Virtio
-attach	virtio at acpinodebus with virtio_acpi
+attach	virtio at acpinodebus with virtio_acpi: virtio_mmio
 file	dev/acpi/virtio_acpi.c		virtio_acpi
 
 # OHCI-compliant USB controller