[backbone-router] add Backbone multicast routing

[simonlingoogle]

This PR uses smcroute to implement multicast forwarding for MLR Listeners.

Major changes include:

• Implement multicast routing using smcroute
  • Install/uninstall smcroute in script/setup
  • Add OTBR_BACKBONE_ROUTER option and otbr-backbone-router library
• Add new Dockerfile ARGs: BACKBONE_ROUTER and NAT64
• Tested by [scripts] add MLR Backbone multicast routing test openthread#5578 (merged)

Suggested merge steps: @jwhui

1. Merge [scripts] add MLR Backbone multicast routing test openthread#5578 using latest commit of this PR, passing all checks
2. Merge this PR using OpenThread master, passing all checks, after [scripts] add MLR Backbone multicast routing test openthread#5578 is merged

[codecov]

Codecov Report

Merging #532 into master will decrease coverage by 0.23%.
The diff coverage is 44.44%.

@@            Coverage Diff             @@
##           master     #532      +/-   ##
==========================================
- Coverage   76.82%   76.59%   -0.24%     
==========================================
  Files          70       74       +4     
  Lines        4885     4905      +20     
==========================================
+ Hits         3753     3757       +4     
- Misses       1132     1148      +16     

Impacted Files	Coverage Δ
src/agent/agent_instance.hpp	100.00% <ø> (ø)
src/agent/border_agent.hpp	100.00% <ø> (ø)
src/agent/ncp.hpp	100.00% <ø> (ø)
src/agent/ncp_openthread.cpp	77.92% <ø> (ø)
src/agent/ncp_openthread.hpp	100.00% <ø> (ø)
src/common/code_utils.hpp	100.00% <ø> (ø)
src/common/logging.cpp	27.27% <ø> (-1.73%)	⬇️
src/common/types.cpp	0.00% <0.00%> (ø)
src/utils/system_utils.cpp	0.00% <0.00%> (ø)
src/agent/agent_instance.cpp	100.00% <100.00%> (ø)
... and 10 more

---

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[bukepo]

LGTM:+1:

[simonlingoogle]

The raspbian-check is constantly failing:

/usr/bin/ranlib: third_party/openthread/repo/src/core/libopenthread-ftd.a: No space left on device
[278/332] Building C object third_party/http-parser/CMakeFiles/http_parser.dir/repo/http_parser.c.o
FAILED: third_party/http-parser/CMakeFiles/http_parser.dir/repo/http_parser.c.o 
/usr/bin/cc  -I../../third_party/http-parser/repo -g -Wall -Wextra -Werror -Wfatal-errors -Wno-missing-braces -std=gnu99 -MD -MT third_party/http-parser/CMakeFiles/http_parser.dir/repo/http_parser.c.o -MF third_party/http-parser/CMakeFiles/http_parser.dir/repo/http_parser.c.o.d -o third_party/http-parser/CMakeFiles/http_parser.dir/repo/http_parser.c.o -c ../../third_party/http-parser/repo/http_parser.c
../../third_party/http-parser/repo/http_parser.c:2575:1: fatal error: error writing to /tmp/ccgLbYAG.s: No space left on device
 }
 ^
compilation terminated.
[279/332] Building C object third_party/cJSON/repo/CMakeFiles/cjson.dir/cJSON.c.o
FAILED: third_party/cJSON/repo/CMakeFiles/cjson.dir/cJSON.c.o 
/usr/bin/cc -DCJSON_API_VISIBILITY -DCJSON_EXPORT_SYMBOLS -DENABLE_LOCALES -I../../third_party/cJSON/repo -fvisibility=hidden  -g -Wall -Wextra -Werror -Wfatal-errors -Wno-missing-braces -std=gnu99 -MD -MT third_party/cJSON/repo/CMakeFiles/cjson.dir/cJSON.c.o -MF third_party/cJSON/repo/CMakeFiles/cjson.dir/cJSON.c.o.d -o third_party/cJSON/repo/CMakeFiles/cjson.dir/cJSON.c.o -c ../../third_party/cJSON/repo/cJSON.c
../../third_party/cJSON/repo/cJSON.c:3096:1: fatal error: error writing to /tmp/ccoYCJkz.s: No space left on device
 }
 ^
compilation terminated.
ninja: build stopped: subcommand failed.

Any one has a clue? @bukepo @jwhui

The issue is now fixed by ryankurte/docker-rpi-emu#21. Previously we never successfully expanded the raspbian image by 1024MB.
Now all checks are passed.