AMDGPU: Remove unnecessary assert

These shouldn't ever be null. The number of successors
was already asserted to be 2.

llvm-svn: 245132
diff --git a/llvm/lib/Target/AMDGPU/SIFixSGPRLiveRanges.cpp b/llvm/lib/Target/AMDGPU/SIFixSGPRLiveRanges.cpp
index a31a9d2..b469898 100644
--- a/llvm/lib/Target/AMDGPU/SIFixSGPRLiveRanges.cpp
+++ b/llvm/lib/Target/AMDGPU/SIFixSGPRLiveRanges.cpp
@@ -156,7 +156,7 @@
       NCD = PDT->findNearestCommonDominator(*NCD->succ_begin(),
                                             *(++NCD->succ_begin()));
     }
-    assert(SuccA && SuccB);
+
     for (std::pair<unsigned, LiveRange*> RegLR : SGPRLiveRanges) {
       unsigned Reg = RegLR.first;
       LiveRange *LR = RegLR.second;