[InlineFunction] Don't add lifetime markers for zero-sized allocas.

This commit fixes the code which adds lifetime markers in InlineFunction to skip
zero-sized allocas instead of asserting on them.

rdar://problem/20531155


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235312 91177308-0d34-0410-b5e6-96231b3b80d8
2 files changed