xen/balloon: Fix compile errors - missing header files.

With a specific enough .config file compile errors show
for missing workqueue declarations.

Reported-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
This commit is contained in:
Konrad Rzeszutek Wilk 2011-07-22 14:01:16 -04:00
commit 0642d2edc8