Another hotfix 7.0.2, this time for win64 msvc

[Reini Urban]

I fixed serious 2 regressions on win64 with msvc, and one new bug in
native_pbc, which would deserve an immediate hotfix.

See
https://github.com/parrot/parrot/issues?q=milestone%3A7.0.2+is%3Aclosed

I never had such a platform to test. jnthn notified me of the regressions.
I installed now win64 msvc (cl 17) and could repro and fix the
outstanding issues.

- win64: fix nci call regression, msvc only. #1190
    On win64 with msvc the size of long is 4.
    Broken with 6.11.0

- msvc: sal does not work cl < 16.0 as such #1192

Visual Studio 9 (cl 15.00) emits [returnvalue:SA_Post(MustCheck=SA_Yes)]
checks and similar which fails to parse somehow.
This is a regression from 6.10. I added better sal checks in 6.11
Windows MSVC with cl < 17.00 only

- [nativbe_pbc] fix win64 cvt_num16_num8 #1193
  on intel assume we use intel 10-byte, not __float128. thus use
cvt_num12_num8, not the 16 byte variant

The problem is the minimization, as I could not test on win64 with a
msvc compiled perl, only with the strawberry mingw perl, and this
combination required more fixes.
I believe that not many people do have a true msvc perl on win64, more
are using the strawberry perl, and will therefore need a bunch of
moire fixes from the branch `smoke-me/win64-msvc-gh1190`, which tested
ok.

So 7.0.2 will be based on 3485324, which fixes some more issues:
inter::progs for msvc,
hints::mswin32 for msvc,
cc_run: add optional exit_code,
icuheaders probe fixes,
smoke-me/gcc_cmpxchg-gh1173 (add atomics),
Optimize away ExtUtils::Command on posix systems #1177

This is the state which was properly tested.

On sunday Larry will present perl6, and I want rakudo being updated
with 7.0.2, for win64 msvc folks.
The plan is for a release tomorrow.
-- 
Reini