[clang] [LoongArch] Fix '-mno-lsx' option not disabling LASX feature (PR #143821)

[Lu Weining via cfe-commits]

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@@ -946,6 +946,8 @@
 // RUN:   | FileCheck --match-full-lines --check-prefix=MNO-LSX %s
 // RUN: %clang --target=loongarch64 -mno-lasx -mno-lsx -x c -E -dM %s -o - \
 // RUN:   | FileCheck --match-full-lines --check-prefix=MNO-LSX %s
+// RUN: %clang --target=loongarch64 -march=la464 -mno-lsx -x c -E -dM %s -o - \
+// RUN:   | FileCheck --match-full-lines --check-prefix=MNO-LSX %s
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SixWeining wrote:

Also test switching these 2 options's order (i.e. `-mno-lsx -march=la464`).

https://github.com/llvm/llvm-project/pull/143821