ofproto-dpif-upcall: Mirror packets that are modified. #2178

Job	Run time
osx clang --disable-ssl	3m 50s
dpdk gcc	11s
linux deb no dpdk	8m 26s
linux gcc --disable-ssl	3m 56s
linux clang --disable-ssl	3m 42s
linux gcc test	9m 55s
linux clang test asan	19m 59s
linux clang test ubsan	10m 57s
linux gcc test --enable-shared	14m 45s
linux clang test --enable-shared	17m 43s
linux gcc test dpdk	10m 58s
linux clang test dpdk	11m 41s
linux gcc test -ljemalloc	11m 0s
linux clang test -ljemalloc	10m 35s
linux gcc --enable-afxdp	3m 15s
linux clang --enable-afxdp	3m 38s
linux gcc dpdk --enable-shared	5m 4s
linux clang dpdk --enable-shared	5m 30s
linux gcc dpdk-shared	5m 14s
linux clang dpdk-shared	4m 1s
linux gcc dpdk-shared --enable-shared	4m 50s
linux clang dpdk-shared --enable-shared	4m 47s
linux gcc m32 --disable-ssl	4m 31s
	2h 58m 28s

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