Testcase and fix for bug 24074

Summary:
In bug 24074, the type information is not shown
correctly. This commit  includes the following -
-> Changes for displaying correct type based on
   current lexical scope for the command "image
   lookup -t"
-> The corresponding testcase.

Reviewers: jingham, ovyalov, spyffe, richard.mitton, clayborg

Differential Revision: http://reviews.llvm.org/D12404

llvm-svn: 248366