Fuzz checker CI: Use more generic include dir for fuzzer includes

Reviewed-by: Hugo Landau <hlandau@openssl.org>
Reviewed-by: Richard Levitte <levitte@openssl.org>
Reviewed-by: Paul Dale <pauli@openssl.org>
(Merged from openssl#19860)

.github/workflows/fuzz-checker.yml

@@ -26,15 +26,15 @@ jobs:
           }, {
             name: libFuzzer,
             config: enable-fuzz-libfuzzer enable-asan enable-ubsan,
-            libs: --with-fuzzer-lib=/usr/lib/llvm-12/lib/libFuzzer.a --with-fuzzer-include=/usr/lib/llvm-12/build/lib/clang/12.0.0/include/fuzzer,
+            libs: --with-fuzzer-lib=/usr/lib/llvm-12/lib/libFuzzer.a --with-fuzzer-include=/usr/include/clang/12/include/fuzzer,
             install: libfuzzer-12-dev,
             cc: clang-12,
             linker: clang++-12,
             tests: -test_memleak
           }, {
             name: libFuzzer+,
             config: enable-fuzz-libfuzzer enable-asan enable-ubsan -fsanitize-coverage=trace-cmp -DFUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION,
-            libs: --with-fuzzer-lib=/usr/lib/llvm-12/lib/libFuzzer.a --with-fuzzer-include=/usr/lib/llvm-12/build/lib/clang/12.0.0/include/fuzzer,
+            libs: --with-fuzzer-lib=/usr/lib/llvm-12/lib/libFuzzer.a --with-fuzzer-include=/usr/include/clang/12/include/fuzzer,
             extra: enable-fips enable-ec_nistp_64_gcc_128 -fno-sanitize=alignment enable-tls1_3 enable-weak-ssl-ciphers enable-rc5 enable-md2 enable-ssl3 enable-ssl3-method enable-nextprotoneg,
             install: libfuzzer-12-dev,
             cc: clang-12,