EXPERIMENTAL STATUS!
To try things out: Define TERMUX_UNIFIED_HEADERS=1 and build to
use the new unified headers.
This causes ndk_patches_unified/ to be used to patch the NDK header
files instead of ndk_patches/.
The pw_getcos field on struct passwd is defined on 64-bit builds
but is NULL which programs does not handle (at least no openssh
which crashes). Initialize this field to "" to avoid this.