[BUGFIX] Seg fault in memory planing for symbolic shape (#2317)

src/relay/backend/graph_plan_memory.cc

@@ -253,12 +253,12 @@ class StorageAllocator : public StorageAllocaBaseVisitor {
     size_t size = 1;
     for (IndexExpr dim : ttype->shape) {
       const int64_t* pval = as_const_int(dim);
-      CHECK_GE(*pval, 0) <<
-        "can not allocate memory for tensor with negative shape" <<
-        *pval;
       CHECK(pval != nullptr)
           << "Cannot allocate memory symbolic tensor shape "
           << ttype->shape;
+      CHECK_GE(*pval, 0)
+          << "Cannot allocate memory for tensor with negative shape"
+          << *pval;
       size *= static_cast<size_t>(pval[0]);
     }
     size *= DivRoundUp(ttype->dtype.bits() * ttype->dtype.lanes(), 8);