[hardware] Fix bug in the DMA's distributed midend #1126

Job	Run time
check-opcodes	8s
riscv-isa-sim	12s
tc-gcc	2m 10s
tc-llvm	4m 9s
verilator	18s
verilator-model (minpool)	2m 59s
verilator-model (mempool)	16m 11s
check-bootrom	19s
build-apps-omp (minpool)	47s
build-apps-gcc (minpool)	1m 6s
build-apps-omp (mempool)	46s
build-apps-gcc (mempool)	1m 29s
tc-halide	30s
build-apps-llvm (minpool)	1m 33s
build-apps-llvm (mempool)	1m 25s
build-apps-halide (minpool)	1m 24s
build-apps-halide (mempool)	1m 15s
unit-test	2m 52s
run-apps-gcc (minpool)	42s
run-apps-halide (minpool)	41s
run-apps-llvm (minpool)	29s
run-apps-gcc (mempool)	2m 45s
run-apps-halide (mempool)	2m 55s
run-apps-llvm (mempool)	2m 55s
clean-up-compile-runs (minpool)	5s
clean-up	4s
clean-up-compile-runs (mempool)	2s
	50m 11s

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