win32: Cleanup PARTITION handling

Use the WINAPI_PARTITION macro to filter desktop/app flavors.
We use a negated desktop check because the default (for mingw-w64 at
least) is to allow all API by combining desktop + app partitions.
This causes build failures if we were to filter using
WINAPI_PARTITION(WINAPI_FAMILY_APP) because it would always be true, but
those API also require Windows 8 or later, while we only require Vista

Fixes warnings like
../src/hb-blob.cc:572:47: warning: 'WINAPI_FAMILY_PC_APP' is not defined, evaluates to 0 [-Wundef]
 #if defined(WINAPI_FAMILY) && (WINAPI_FAMILY==WINAPI_FAMILY_PC_APP || WINAPI_FAMILY==WINAPI_FAMILY_PHONE_APP)
                                              ^
../src/hb-blob.cc:572:86: warning: 'WINAPI_FAMILY_PHONE_APP' is not defined, evaluates to 0 [-Wundef]
 #if defined(WINAPI_FAMILY) && (WINAPI_FAMILY==WINAPI_FAMILY_PC_APP || WINAPI_FAMILY==WINAPI_FAMILY_PHONE_APP)
3 files changed