cloudmonkey: Simplify missing parameter check
cloudmonkey: Simplify missing parameter check

This simplifies Carson Anderson's previous patch. We simply split by [ and take
the first element, if [ was not present we get the string/key itself.

Signed-off-by: Rohit Yadav <0fa72ca37c4b5fa62675187ce32ea6c9f842fd52@apache.org>

remibergsma/cloudstack-cloudmonkey,remibergsma/cloudstack-cloudmonkey,Interoute/cloudmonkey-interoute,apache/cloudstack-cloudmonkey,apache/cloudstack-cloudmonkey,Interoute/cloudmonkey-interoute