[compiler-rt] [scudo][gwp_asan] Clean up Fuchsia zxtest framework integration (PR #90015)

[Fabio D'Urso via llvm-commits]

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@@ -8,7 +8,7 @@
 
 #include "platform.h"
 
-#if SCUDO_FUCHSIA
+#ifdef LIBC_COPT_TEST_USE_ZXTEST
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fabio-d wrote:

At line 48 too?

https://github.com/llvm/llvm-project/pull/90015