Wrap main function, to set up console before and shutdown after.

Bug: 223166344
Test: Ran unprotected VM under crosvm.
Change-Id: Idf1f9d30a5118737134a31c65375cdc293ede117
diff --git a/vmbase/entry.S b/vmbase/entry.S
index f0021be..a12e1aa 100644
--- a/vmbase/entry.S
+++ b/vmbase/entry.S
@@ -150,7 +150,7 @@
 	msr vbar_el1, x30
 
 	/* Call into Rust code. */
-	bl main
+	bl rust_entry
 
 	/* Loop forever waiting for interrupts. */
 4:	wfi