Extract timeouts to compos_common

Centralise the logic for deciding if we need to allow for nested
virtualization. Put the timeouts in one place to remove
duplication. Extend the logic to composd_cmd which was previously
always using the long timeout (which is very annoying for manual
testing).

Bug: 186126194
Test: Presubmits
Change-Id: I7104fc19616e4c745a11c228ada2a0b5be00e8ed
diff --git a/compos/common/Android.bp b/compos/common/Android.bp
index d8fec81..5893fd6 100644
--- a/compos/common/Android.bp
+++ b/compos/common/Android.bp
@@ -14,6 +14,7 @@
         "libbinder_rpc_unstable_bindgen",
         "libbinder_rs",
         "liblog_rust",
+        "librustutils",
     ],
     shared_libs: [
         "libbinder_rpc_unstable",