Merge bitcoin#22841: ci: Fuzz with -ftrivial-auto-var-init=pattern

fa0a5fa ci: Fuzz with -ftrivial-auto-var-init=pattern (MarcoFalke)

Pull request description:

  This makes memory bugs deterministic. `-ftrivial-auto-var-init=pattern` is incompatible with other memory sanitizers (like valgrind and msan), but that is irrelevant here, because the address sanitizer in this fuzz CI config is already incompatible with them.

  `-ftrivial-auto-var-init=pattern` goes well with `-fsanitize=bool` and `-fsanitize=enum`, but those are already enabled via `-fsanitize=undefined`. See  https://clang.llvm.org/docs/UndefinedBehaviorSanitizer.html#available-checks

ACKs for top commit:
  practicalswift:
    cr ACK fa0a5fa

Tree-SHA512: ed6be953cd99eadb1ba245ba30170747eff66be54d2773c8d26a3a6aee0fdcd6967c596f4f4ab1d238de6a6526623dac5211f0ba77f1986639395d7921bdc19f

ci/test/00_setup_env_native_fuzz.sh

@@ -14,5 +14,5 @@ export RUN_UNIT_TESTS=false
 export RUN_FUNCTIONAL_TESTS=false
 export RUN_FUZZ_TESTS=true
 export GOAL="install"
-export BITCOIN_CONFIG="--enable-fuzz --with-sanitizers=fuzzer,address,undefined,integer CC=clang CXX=clang++"
+export BITCOIN_CONFIG="--enable-fuzz --with-sanitizers=fuzzer,address,undefined,integer CC='clang -ftrivial-auto-var-init=pattern' CXX='clang++ -ftrivial-auto-var-init=pattern'"
 export CCACHE_SIZE=200M