CA-33707: fix bug where the xenstore watching code would fail with Xb EEXIST if the same path was in the watch list multiple times.
CA-33707: fix bug where the xenstore watching code would fail with Xb EEXIST if the same path was in the watch list multiple times.

Signed-off-by: David Scott <63c9eb0ea83039690fefa11afe17873ba8278a56@eu.citrix.com>

koushikcgit/xcp-rrdd,koushikcgit/xcp-rrdd,koushikcgit/xcp-rrdd,djs55/xcp-rrdd,djs55/squeezed,djs55/xcp-networkd,simonjbeaumont/xcp-rrdd,johnelse/xcp-rrdd,sharady/xcp-networkd,djs55/xcp-rrdd,johnelse/xcp-rrdd,koushikcgit/xcp-networkd,robhoes/squeezed,koushikcgit/xcp-networkd,simonjbeaumont/xcp-rrdd,sharady/xcp-networkd,djs55/xcp-networkd