deps: `MASM.UseSafeExceptionHandlers` for OpenSSL

Use `msvs_settings.MASM.UseSafeExceptionHandlers` when building OpenSSL
assembly code on Windows. This option appends `/safeseh` to the list of
assembler flags when building `.asm` files on Windows.

Having this option in place, separate rules in `masm_compile.gypi` are
no longer needed.

Fix: #7426
PR-URL: https://github.com/nodejs/node/pull/7427


Reviewed-By: Ben Noordhuis <info@bnoordhuis.nl>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Bert Belder <bertbelder@gmail.com>