[clang] [clang][hexagon] Add support for -nolibc (PR #67515)

[Fangrui Song via cfe-commits]

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@@ -401,6 +401,30 @@
 // CHECK338-NOT: "--end-group"
 // CHECK338: "{{.*}}/Inputs/hexagon_tree/Tools/bin/../target/hexagon/lib/v60/fini.o"
 
+// RUN: %clangxx -### -target hexagon-unknown-elf \
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MaskRay wrote:

use `--target=` for new tests.
`-target ` has been deprecated since Clang 3.4

https://github.com/llvm/llvm-project/pull/67515