Box64 Cross-compiling: Can I specify where the library files are going?
I'm trying to do some cross-compiles on my devices to target specific ARM64 devices, and I'm having difficulty getting the libraries that Box64 compiles to go into a specific folder. The following is my command line (note the slashes are just to escape the newline):

```
cmake -D CMAKE_C_COMPILER=aarch64-linux-gnu-gcc -D CMAKE_CXX_COMPILER=aarch64-linux-gnu-g++ \ 
-D CMAKE_INSTALL_PREFIX=$(pwd)/box64-rpi -D ARM_DYNAREC=ON -D CMAKE_BUILD_TYPE=RelWithDebInfo \ 
-D RPI3ARM64=1
```
I'll break it down step by step:
- I'm using a x64 host, so I'm using a cross compiler toolchain.
- I want the compiled files to be placed in the CMAKE_INSTALL_PREFIX path, which evaluates to `/workdir/box64-rpi`.
- I'm building a release binary with debug info.
- I'm wanting to use the R-Pi 3 enhancements where possible.

However, with this I find that the box64 binary is copied into `/workdir/box64-rpi/bin` but other stuff gets placed in `/etc` and `/usr/lib`. I want it to be placed in `/workdir/box64-rpi/etc` and `/workdir/box64-rpi/usr/lib`.

What am I doing wrong?