Stop including <sys/sysmacros.h> from <sys/types.h>.

<sys/types.h> unconditionally includes <sys/sysmacros.h>.

<sys/sysmacros.h> defines major, minor, and makedev. In the deprecated NDK
headers, these were inline functions. In the unified headers, they are
function-like macros.

The inline functions would only collide with another function called major,
minor, or makedev but the macros will replace anything with a function-like
form such as definitions of class methods called major, minor, or makedev.
This causes code which has such definitions to fail to compile when moving
from the deprecated headers to the unified headers.

Resolve this by removing the transitive dependency. Folks who want
<sys/sysmacros.h> can ask for it explicitly (it's been in both bionic and
glibc for years, though I don't think macOS has it [as usual]).

Bug: https://github.com/android-ndk/ndk/issues/398
Test: builds
Change-Id: If2921c7b5d979c3066f199f22c64d4d2f7bf6632