cmd/link: add runtime.text.N symbols to macho symbol table in dynlink mode
In dynamic linking mode (e.g. when using plugins) on darwin, the
marker symbols runtime.text and runtime.etext are added to Textp
in an early stage, so when adding symbols to the symbol table we
don't need to explicitly add them. However, when splitting text
sections, the runtime.text.N marker symbols for the addtional
sections are not added to Textp. So we do need to add them
explicitly to the symbol table.
Fixes #66993.
Change-Id: Ic718d03cd71fc0bfb931cff82640b1f4c53b89be
Reviewed-on: https://go-review.googlesource.com/c/go/+/586555
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com> Reviewed-by: Than McIntosh <thanm@google.com>