Actually check read/write errors in IDE (Ian Jackson).

This patch makes the ide emulation actually take notice of
error returns from bdrv_write and bdrv_aio_{read,write}.

(Cherry picked from qemu-xen e0e7a0afe0e324a1f7d64c240f567b15dbe454cf,
 first posted to qemu-devel Wed, 20 Feb 2008 15:26:41 +0000)

Signed-off-by: Ian Jackson <Ian.Jackson@eu.citrix.com>


git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@5368 c046a42c-6fe2-441c-8c8c-71466251a162
