`return_cc_move` should be `static`

[ImpleLee]

This function is supposed to be internal API, but exposed as a global function.

Symbol table '.symtab' contains 113 entries:
   Num:    Value          Size Type    Bind   Vis      Ndx Name
...
   101: 0000000000003570    98 FUNC    GLOBAL DEFAULT   14 return_cc_move
...

[ImpleLee]

Solved.