osd: Fix compile-time warning.
osd: Fix compile-time warning.

store is properly initialized inside a try block, but the
compiler doesn't notice that and so thinks it may be used
uninitialized. So initialize it to be NULL.

Signed-off-by: Greg Farnum <0bcb4295d38ee745130ea5f2bb88ef4eef474e61@dreamhost.com>

ajnelson/ceph,ajnelson/ceph,ajnelson/ceph,ajnelson/ceph,ajnelson/ceph,ajnelson/ceph