[RFC] Homebrew: Compile as release build.

To avoid problems such as #1362.
These are the flags:

```
 CMAKE_C_FLAGS_DEBUG              -g                                                                                                                          
 CMAKE_C_FLAGS_MINSIZEREL         -Os -DNDEBUG                                                                                                                
 CMAKE_C_FLAGS_RELEASE            -O3 -DNDEBUG                                                                                                                
 CMAKE_C_FLAGS_RELWITHDEBINFO     -O2 -g -DNDEBUG                                                                                                             
```

What should we use?