Fix eqlx CLI output parsing on bad input

The eqlx driver would identify CLI command completion
by looking for the system name prompt at the end of
the output ("ARRAY_NAME>"). In some cases where there
is bad input the array will print an error, then
prepopulate the command again so it can be edited,
resulting in the output:

"ARRAY_NAME> [bad command]"

The array name prompt only gets printed on command
completion, so the fix is to look for the prompt
anywhere in the CLI output.

Change-Id: I063a203c9746689ca8a42a97725b059f782e3812
Closes-Bug: 1378394
Merge "Fix eqlx CLI output parsing on bad input"