adb: win32: fix StringPrintf format string checking of %zd and PRIu64

At runtime, vsnprintf (and android::base::StringPrintf which calls it)
call a mingw version of vsnprintf, not the vsnprintf from MSVCRT.DLL.
The mingw version properly understands %zd and PRIu64 (the latter,
provided that you #include <inttypes.h>).

The problem was that android::base::StringPrintf was causing
compile-time errors saying that %zd and PRIu64 were not recognized. It
seems that this was because the attribute on the function prototypes
specified `printf' instead of `gnu_printf'. Once that was fixed to match
vsnprintf's attribute, the warnings went away.

This uses similar preprocessor techniques as <android/log.h>.

Also restore a %zd usage to avoid a static_cast<>, and make
print_transfer_progress()'s format string compile-time checkable (and
tweak some types and %llu => PRIu64).

Change-Id: I80b31b9994858a28cb7c6847143b86108b8ab842
Signed-off-by: Spencer Low <CompareAndSwap@gmail.com>