same as r65275 but for call cache.

=== Optcarrot Benchmark ===
$ benchmark-driver benchmark.yml --rbenv 'before::before --disable-gems --jit;after::after --disable-gems --jit' -v --repeat-count 24
before: ruby 2.6.0dev (2018-10-21 trunk 65277) +JIT [x86_64-linux]
after: ruby 2.6.0dev (2018-10-21 trunk 65277) +JIT [x86_64-linux]
last_commit=mjit.c: copy call cache values to MJIT worker
Calculating -------------------------------------
                             before       after
Optcarrot Lan_Master.nes     85.372      85.359 fps

Comparison:
             Optcarrot Lan_Master.nes
                  before:        85.4 fps
                   after:        85.4 fps - 1.00x  slower

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@65279 b2dd03c8-39d4-4d8f-98ff-823fe69b080e