[compiler-rt] Update libFuzzer build script to use C++17. (#89604)

libFuzzer uses std::clamp which was introduced in C++17.

Author: fcambus

compiler-rt/lib/fuzzer/build.sh

@@ -2,7 +2,7 @@
 LIBFUZZER_SRC_DIR=$(dirname $0)
 CXX="${CXX:-clang}"
 for f in $LIBFUZZER_SRC_DIR/*.cpp; do
-  $CXX -g -O2 -fno-omit-frame-pointer -std=c++14 $f -c &
+  $CXX -g -O2 -fno-omit-frame-pointer -std=c++17 $f -c &
 done
 wait
 rm -f libFuzzer.a