runtime: move osinit to Go
This is a step toward updating libgo to 1.13. This adds the 1.13
version of the osinit function to Go code, and removes the
corresponding code from the C runtime. This should simplify future updates.
Some additional 1.13 code was brought in to simplify this change.
Reviewed-by: Than McIntosh <email@example.com>
Reviewed-by: Cherry Zhang <firstname.lastname@example.org>
29 files changed