virtiofs: Add systemd unit to mount virtiofs inside guest

1: Add systemd unit which mount virtiofs emulted mount point
under /mnt/shared

2: Add the configs to vm_config.json

Bug: 372171883
Test: Verify virtiofs mounts inside Terminal App under /mnt/shared
Change-Id: I66d9798701d539e265890a99ced4a1b6478324ff
Signed-off-by: Akilesh Kailash <akailash@google.com>
diff --git a/build/debian/vm_config.json.x86_64 b/build/debian/vm_config.json.x86_64
index 2fb9faa..8a491e4 100644
--- a/build/debian/vm_config.json.x86_64
+++ b/build/debian/vm_config.json.x86_64
@@ -7,6 +7,14 @@
             "writable": true
         }
     ],
+    "sharedPath": [
+        {
+            "sharedPath": "/storage/emulated"
+        },
+        {
+            "sharedPath": "/data/data/com.google.android.virtualization.terminal/files"
+        }
+    ],
     "kernel": "$PAYLOAD_DIR/vmlinuz",
     "initrd": "$PAYLOAD_DIR/initrd.img",
     "params": "root=/dev/vda1",