vmxnet3: Do not depend on PC

vmxnet3 has no dependency on PC, and VMware Fusion actually makes it
available on Apple Silicon according to:
https://kb.vmware.com/s/article/90364

Signed-off-by: Akihiko Odaki <akihiko.odaki@daynix.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Jason Wang <jasowang@redhat.com>

hw/net/Kconfig

@@ -56,7 +56,7 @@ config RTL8139_PCI
 
 config VMXNET3_PCI
     bool
-    default y if PCI_DEVICES && PC_PCI
+    default y if PCI_DEVICES
     depends on PCI
 
 config SMC91C111