[LLDB] Add missing newline to "image lookup" output

When using --name, due to a missing newline, multiple symbol results
were not correctly printed:
```
(lldb) image lookup -r -n "As<.*"
2 matches found in <...>/tbi_lisp:
        Address: tbi_lisp<...>
        Summary: tbi_lisp<...> at Symbol.cpp:75        Address: tbi_lisp<...>
        Summary: tbi_lisp<...> at Symbol.cpp:82
```
It should be:
```
(lldb) image lookup -r -n "As<.*"
2 matches found in /home/david.spickett/tbi_lisp/tbi_lisp:
        Address: tbi_lisp<...>
        Summary: tbi_lisp<...> at Symbol.cpp:75
        Address: tbi_lisp<...>
        Summary: tbi_lisp<...> at Symbol.cpp:82
```
With Address/Summary on separate lines.

Reviewed By: clayborg, labath

Differential Revision: https://reviews.llvm.org/D143564