Make INLINE pragmas for pattern synonyms work with TH
Previously, the code for converting INLINE <name> pragmas from TH splices
used vNameN, which assumed that <name> must live in the variable namespace.
Pattern synonyms, on the other hand, live in the constructor namespace, which caused the issue seen in #23203 (closed). I've
fixed the issue by switching to vcNameN instead, which works for both the
variable and constructor namespaces.
Fixes #23203 (closed).