This moves library functions used by both QEMU and the QEMU tools,
such as qemu-img, qemu-nbd etc. from osdep.c to oslib-{posix,win32}.c
In addition it introduces oslib-obj.y to the Makefile set to be
included by the various targets, instead of relying on these library
functions magically getting included via block-obj-y.
Signed-off-by: Jes Sorensen <Jes.Sorensen@redhat.com>
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>