We were using two instructions for similar purpose : break and
predicated break. Only predicated_break was emitted and it was
lowered at R600ControlFlowFinalizer to JUMP;CF_BREAK;POP.
This commit simplify the situation by making AMDILCFGStructurizer
emit IF_PREDICATE;BREAK;ENDIF; instead of predicated_break (which
is now removed).
There is no functionality change.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@187510 91177308-0d34-0410-b5e6-96231b3b80d8