[build] fix some build breaks on Ubuntu 18.04

[leeminghao]

Signed-off-by: liminghao liminghao@xiaomi.com

[KKomarov]

add #include <sys/sysmacros.h> to qga/commands-posix.c to fix major minor error

[leeminghao]

add #include <sys/sysmacros.h> to qga/commands-posix.c to fix major minor error

I don't know how to understand this tip

[KKomarov]

I've tried to compile on latest debian, it has new libc with breaking change:

• The inclusion of <sys/sysmacros.h> by <sys/types.h> is deprecated.
  This means that in a future release, the macros “major”, “minor”, and
  “makedev” will only be available from <sys/sysmacros.h>.

  These macros are not part of POSIX nor XSI, and their names frequently
  collide with user code; see for instance glibc bug 19239 and Red Hat
  bug 130601. <stdlib.h> includes <sys/types.h> under _GNU_SOURCE, and
  C++ code presently cannot avoid being compiled under _GNU_SOURCE,
  exacerbating the problem.

During compile I got Identifier not found. To fix it just add add #include <sys/sysmacros.h> to qga/commands-posix.c