Follow the name change of _CheckHostnameSane
Follow the name change of _CheckHostnameSane

When cmdlib/instance.py was split, the functions used over
the split were no longer internal and hence got renamed to
a non-internal name. When following code in a merge path,
we have to do this renaming as well. So do it now.

Signed-off-by: Klaus Aehlig <4ce51de36d9068cd7db2eec1151e0f3f95419008@google.com>
Reviewed-by: Helga Velroyen <2d0126b1ec6f9ec5cbec4a7012aa14faeaef10f5@google.com>

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