A module referenced with srcs: ":module" was not honoring
ALLOW_MISSING_DEPENDENCIES=true. Don't fail if the module
doesn't exist, an error will already have been produced by
ExtractSourcesDeps.
Bug: 68183622
Test: m ALLOW_MISSING_DEPENDENCIES=true
Change-Id: Id806633d12ab2ecd78b532e1922e59824e5c20a8