Add check for setcap existence
Add check for setcap existence

This patch modifies the daemon-util to check if setcap is present
before attempting to use it.

Signed-off-by: Hrvoje Ribicic <be5828fca31f89218048bec4189e30a581aa65da@google.com>
Reviewed-by: Klaus Aehlig <4ce51de36d9068cd7db2eec1151e0f3f95419008@google.com>

bitemyapp/ganeti,onponomarev/ganeti,andir/ganeti,grnet/snf-ganeti,leshchevds/ganeti,bitemyapp/ganeti,onponomarev/ganeti,mbakke/ganeti,yiannist/ganeti,ganeti/ganeti,mbakke/ganeti,andir/ganeti,leshchevds/ganeti,ganeti/ganeti,leshchevds/ganeti,grnet/snf-ganeti,ganeti/ganeti,andir/ganeti,mbakke/ganeti,yiannist/ganeti,yiannist/ganeti