Feedback from review: add '-lrt' if CHPL_LLVM!='none', not if =='llvm'.
Feedback from review: add '-lrt' if CHPL_LLVM!='none', not if =='llvm'.

CoryMcCartan/chapel,chizarlicious/chapel,chizarlicious/chapel,hildeth/chapel,CoryMcCartan/chapel,hildeth/chapel,hildeth/chapel,CoryMcCartan/chapel,hildeth/chapel,hildeth/chapel,chizarlicious/chapel,hildeth/chapel,CoryMcCartan/chapel,chizarlicious/chapel,chizarlicious/chapel,hildeth/chapel,CoryMcCartan/chapel,chizarlicious/chapel,CoryMcCartan/chapel,CoryMcCartan/chapel,chizarlicious/chapel