Most modern Unix environments use 64-bit off_t by default: OpenBSD,
FreeBSD, OS X, and Linux libc implementations such as Musl.

glibc is the lone exception; it can default to 32 bits but this is
configurable by setting _FILE_OFFSET_BITS.

Avoiding the stat64()/fstat64() interfaces is desirable because they
are nonstandard and not implemented on many systems (including
OpenBSD and FreeBSD), and using 64 bits for stat()/fstat() is either
the default or trivial to set up.

src/common/file_util.cpp:79:19: error: variable has incomplete type 'struct stat64'
    struct stat64 file_info;
                  ^
src/common/file_util.cpp:79:12: note: forward declaration of 'stat64'
    struct stat64 file_info;
           ^
src/common/file_util.cpp:99:19: error: variable has incomplete type 'struct stat64'
    struct stat64 file_info;
                  ^
src/common/file_util.cpp:99:12: note: forward declaration of 'stat64'
    struct stat64 file_info;
           ^
src/common/file_util.cpp:342:19: error: variable has incomplete type 'struct stat64'
    struct stat64 buf;
                  ^
src/common/file_util.cpp:342:12: note: forward declaration of 'stat64'
    struct stat64 buf;
           ^
src/common/file_util.cpp:359:19: error: variable has incomplete type 'struct stat64'
    struct stat64 buf;
                  ^
src/common/file_util.cpp:359:12: note: forward declaration of 'stat64'
    struct stat64 buf;
           ^
4 errors generated.

This makes clang-format useful on those.

Also add a bunch of forgotten transitive includes, which otherwise
prevented compilation.

ForeachDirectoryEntry didn't actually do anything with the `recursive`
parameter, and the corresponding callback parameter was shadowing the
actual recursion counters in the user functions.

Fixes #1115.

Also improves the performances of DiskArchive’s directory
implementation a lot, simply by not going through the entire tree
instead of just listing the first level files.

Thanks to JayRoxFox for rebasing this on current master!

ForeachDirectoryEntry is changed by #1256 ,but return value at last line
was missing.

ScanDirectoryTreeAndCallback, before this change, coupled error/return
codes and actual return values (number of entries found). This caused
confusion and difficulty interpreting the precise way the function
worked.

Supersedes, and closes #1255.

Converted FileUtil::ScanDirectoryTree and FileUtil::DeleteDirRecursively
to use the new ScanDirectoryTreeAndCallback function internally.

This allows for easily movable and independent configuration and data directories, using standardized paths.

Each archive now takes a mount point of either NAND or SDMC, and builds its own directory structure there, trying to simulate an HLE-friendly hardware layout

This is to better represent the hardware layout, they are still aren't quite accurate, but this better and will help a bit when implementing the other archives like NAND-RO and NAND-RW

Fixed a few warnings and cleaned up the code