[PM] Rename lookupPass to lookUpPass.

Summary:
"Lookup" is a noun ("lookup table"), "look up" is a verb ("look up
'table' in the dictionary").

Reviewers: chandlerc

Subscribers: silvas, llvm-commits, mehdi_amini

Differential Revision: https://reviews.llvm.org/D27374

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@288598 91177308-0d34-0410-b5e6-96231b3b80d8
1 file changed