Unrolled build for rust-lang#130047

Rollup merge of rust-lang#130047 - ChrisDenton:win-dbghelp, r=wesleywiser

Win: Add dbghelp to the list of import libraries

This is used by the backtrace crate. But we use a submodule to include backtrace in std (rather than being a real crate) so we need to add the dependency here.

Author: rust-timer

library/windows_targets/src/lib.rs

@@ -38,4 +38,5 @@ pub macro link {
 #[link(name = "ntdll")]
 #[link(name = "userenv")]
 #[link(name = "ws2_32")]
+#[link(name = "dbghelp")] // required for backtrace-rs symbolization
 extern "C" {}