[clang] [Driver] Add LTO support for NetBSD (PR #187923)

[Fangrui Song via cfe-commits]

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@@ -24,6 +24,8 @@
 // RUN: %clang --target=x86_64-unknown-linux -save-stats -flto -o obj/dir/save-stats.exe -Wl,-plugin-opt=-dummy %s -### 2>&1 | FileCheck %s -check-prefix=CHECK-LTO
 // RUN: %clang --target=x86_64-unknown-freebsd -save-stats -flto -o obj/dir/save-stats.exe %s -### 2>&1 | FileCheck %s -check-prefix=CHECK-LTO
 // RUN: %clang --target=x86_64-unknown-freebsd -save-stats -flto -o obj/dir/save-stats.exe -Wl,-plugin-opt=-dummy %s -### 2>&1 | FileCheck %s -check-prefix=CHECK-LTO
+// RUN: %clang --target=x86_64-unknown-netbsd -save-stats -flto -o obj/dir/save-stats.exe %s -### 2>&1 | FileCheck %s -check-prefix=CHECK-LTO
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MaskRay wrote:

Unneeded. It's an antipattern to every OS in this test.

https://github.com/llvm/llvm-project/pull/187923