Change interface for TargetLowering::LowerCallTo and TargetLowering::LowerCall

Change interface for TargetLowering::LowerCallTo and TargetLowering::LowerCall
to pass around a struct instead of a large set of individual values.  This
cleans up the interface and allows more information to be added to the struct
for future targets without requiring changes to each and every target.

NV_CONTRIB

llvm-svn: 157479