Rollup merge of #133631 - flba-eb:add_nto_qnx71_iosock_support, r=workingjubilee

Support QNX 7.1 with `io-sock`+libstd and QNX 8.0 (`no_std` only)

Changes of this pull request:

1. Refactor code for qnx nto targets to share more code in file `nto_qnx.rs`
1. Add support for an additional network stack on nto qnx 7.1.

   QNX 7.1 supports two network stacks:

   1. `io-pkt`, which is default
   2. `io-sock`, which is optional on 7.1 but default in QNX 8.0

   As one can see in the [io-sock migration notes](https://www.qnx.com/developers/docs/7.1/index.html#com.qnx.doc.neutrino.io_sock/topic/migrate_app.html), this changes the libc API in a way similar to e.g. linux-gnu vs. linux-musl.

   This change adds a new target which has a different value for `target_env`, so that e.g. libc can distinguish between both APIs.

2. Add initial support for QNX 8.0, thanks to AkhilTThomas. As it turned out, the problem with forking many processes still exists in QNX 8.0. Because if this, we are now using it for any QNX version (i.e. not check for `target_env` anymore).

1 files changed, 4 insertions, 0 deletions

diff --git a/src/bootstrap/src/core/sanity.rs b/src/bootstrap/src/core/sanity.rs
index ed0155622c2..6c8cda18548 100644
--- a/src/bootstrap/src/core/sanity.rs
+++ b/src/bootstrap/src/core/sanity.rs
@@ -34,6 +34,10 @@ pub struct Finder {
 // Targets can be removed from this list once they are present in the stage0 compiler (usually by updating the beta compiler of the bootstrap).
 const STAGE0_MISSING_TARGETS: &[&str] = &[
     // just a dummy comment so the list doesn't get onelined
+    "aarch64-unknown-nto-qnx710_iosock",
+    "x86_64-pc-nto-qnx710_iosock",
+    "x86_64-pc-nto-qnx800",
+    "aarch64-unknown-nto-qnx800",
 ];
 
 /// Minimum version threshold for libstdc++ required when using prebuilt LLVM