[compiler-rt][Fuchsia] Support HWASan on Fuchsia

[leonardchan]

Summary

This allows for hwasan to be built targetting fuchsia.

[mcgrathr]

I think this may need to be about the last thing to actually land. It shouldn't land before building the runtime reliably works without error, and I think we should land any refactoring of the runtime we needed in preparation for Fuchsia-specific changes before landing anything Fuchsia-specific to make it compile.

compiler-rt/cmake/config-ix.cmake

 if (COMPILER_RT_HAS_SANITIZER_COMMON AND MSAN_SUPPORTED_ARCH AND
     OS_NAME MATCHES "Linux|FreeBSD|NetBSD")
   set(COMPILER_RT_HAS_MSAN TRUE)
 else()
   set(COMPILER_RT_HAS_MSAN FALSE)
 endif()
 
 if (COMPILER_RT_HAS_SANITIZER_COMMON AND HWASAN_SUPPORTED_ARCH AND
-    OS_NAME MATCHES "Linux|Android")
+    OS_NAME MATCHES "Linux|Android|Fuchsia")
   set(COMPILER_RT_HAS_HWASAN TRUE)
 else()
   set(COMPILER_RT_HAS_HWASAN FALSE)
 endif()
 
 if (COMPILER_RT_HAS_SANITIZER_COMMON AND MEMPROF_SUPPORTED_ARCH AND
     OS_NAME MATCHES "Linux")
   set(COMPILER_RT_HAS_MEMPROF TRUE)