Merge commit 'qemu-svn/trunk'

Merge commit 'qemu-svn/trunk'

* commit 'qemu-svn/trunk': (27 commits)
  gdbstub: Allow re-instantiation (Jan Kiszka)
  char: Fix closing of various char devices (Jan Kiszka)
  qemu-img: adding a "-F base_fmt" option to "qemu-img create -b" (Uri Lublin)
  block-qcow2: keep backing file format in a qcow2 extension (Uri Lublin)
  block: support known backing format for image create and open (Uri Lublin)
  Introducing qcow2 extensions (Uri Lublin)
  kvm: Drop kvm_patch_opcode_byte (Jan Kiszka)
  ROM write access for debugging (Jan Kiszka)
  Use the DMA api to map virtio elements.
  virtio-blk: use generic vectored I/O APIs (Christoph Hellwig)
  add qemu_iovec_init_external (Christoph Hellwig)
  Clean some PCI defines (Stefan Weil)
  Fix monitor command (screendump) (Stefan Weil)
  Remove nodisk_ok machine feature (Jan Kiszka)
  musicpal: Fix regression caused by 6839 (Jan Kiszka)
  gdbstub: Drop redundant memset after qemu_mallocz (Jan Kiszka)
  get roms more room. (Glauber Costa)
  new scsi-generic abstraction, use SG_IO (Christoph Hellwig)
  Document sun ID PROM contents
  Fix DMA API when handling an immediate error from block layer (Avi Kivity)
  ...

Conflicts:
	qemu/hw/pc.c
	qemu/hw/pci.h
	qemu/hw/virtio.c
	qemu/qemu-doc.texi
	qemu/vl.c

Signed-off-by: Avi Kivity <avi@redhat.com>