RFR: JDK-8300531: MSVC CFlags look suspicious

[Justin King]

Update MSVC CFlags to be more consistent with other compilers. Also disables RTTI in a simliar manner to GCC/Clang for the JVM.

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Commit messages:
 - Update MSVC CFlags

Changes: https://git.openjdk.org/jdk/pull/12073/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=12073&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8300531
  Stats: 13 lines in 1 file changed: 6 ins; 0 del; 7 mod
  Patch: https://git.openjdk.org/jdk/pull/12073.diff
  Fetch: git fetch https://git.openjdk.org/jdk pull/12073/head:pull/12073

PR: https://git.openjdk.org/jdk/pull/12073