os: Remove deprecated malloc/free wrappers, clean {X,XNF}{alloc,calloc,realloc,free,strdup} from pre-C89 baggage

 Backported from X.org:

 commit cad9b053d52f62432dfd70e42e0240de77027cae
 Author: Adam Jackson <ajax@redhat.com>
 Date:   Tue Jul 8 13:24:25 2014 -0400

    os: Remove deprecated malloc/free wrappers
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Adam Jackson <ajax@redhat.com>

 commit e983848ab44b0769f97f6207f1aa8b4f127be6a9
 Author: Mikhail Gusarov <dottedmag@dottedmag.net>
 Date:   Thu May 6 00:16:24 2010 +0700

    Clean {X,XNF}{alloc,calloc,realloc,free,strdup} from pre-C89 baggage

    C89 guarantees alignment of pointers returned from malloc/calloc/realloc, so
    stop fiddling with alignment manually and just pass the arguments to library
    functions.

    Also convert silent error when negative size is passed into function into
    warning in log file.
Signed-off-by: Mikhail Gusarov <dottedmag@dottedmag.net>
Reviewed-by: Peter Hutterer <peter.hutterer@who-t.net>

 Backport to nx-libs: Mike Gabriel <mike.gabriel@das-netzwerkteam.de>