broadcom master image build broken for >10 days

[daall]

Description
https://sonic-jenkins.westus2.cloudapp.azure.com/job/broadcom/job/buildimage-brcm-all/ has broken for several days.

Steps to reproduce the issue:
https://sonic-jenkins.westus2.cloudapp.azure.com/job/broadcom/job/buildimage-brcm-all/448/
https://sonic-jenkins.westus2.cloudapp.azure.com/job/broadcom/job/buildimage-brcm-all/450/
https://sonic-jenkins.westus2.cloudapp.azure.com/job/broadcom/job/buildimage-brcm-all/452/
(and others)

Describe the results you received:
(trimmed for brevity, see one of the above links for full failure output)

14:11:21.851  g++ -I/usr/include/sai -I. -std=c++11 -DFORCE_BOOST_SMART_PTR -c src/gen-cpp/switch_sai_rpc.cpp -o src/obj/switch_sai_rpc.o
14:11:21.851  g++ -I/usr/include/sai -I. -std=c++11 -DFORCE_BOOST_SMART_PTR -c src/gen-cpp/switch_sai_types.cpp -o src/obj/switch_sai_types.o
14:11:21.851  g++ -I/usr/include/sai -I. -std=c++11 -DFORCE_BOOST_SMART_PTR -c src/gen-cpp/switch_sai_constants.cpp -o src/obj/switch_sai_constants.o
14:11:21.851  g++ -I/usr/include/sai -I. -std=c++11 -DFORCE_BOOST_SMART_PTR -c src/switch_sai_rpc_server.cpp -o src/obj/switch_sai_rpc_server.o -I/usr/include/sai -I. -std=c++11 -DFORCE_BOOST_SMART_PTR -I./src/gen-cpp
14:11:21.851  src/switch_sai_rpc_server.cpp:48:17: fatal error: sai.h: No such file or directory
14:11:21.851   #include <sai.h>
14:11:21.851                   ^
14:11:21.851  compilation terminated.
14:11:21.851  Makefile:81: recipe for target 'src/obj/switch_sai_rpc_server.o' failed
14:11:21.851  make[4]: *** [src/obj/switch_sai_rpc_server.o] Error 1
14:11:21.851  make[4]: Leaving directory '/sonic/src/sonic-sairedis/SAI/test/saithrift'
14:11:21.851  Makefile:29: recipe for target 'saithrift-build' failed
14:11:21.851  make[3]: *** [saithrift-build] Error 2
14:11:21.851  make[3]: Leaving directory '/sonic/src/sonic-sairedis/SAI'
14:11:21.851  debian/rules:26: recipe for target 'override_dh_auto_build' failed
14:11:21.851  make[2]: *** [override_dh_auto_build] Error 2
14:11:21.851  make[2]: Leaving directory '/sonic/src/sonic-sairedis/SAI'
14:11:21.851  debian/rules:23: recipe for target 'build' failed
14:11:21.851  make[1]: *** [build] Error 2
14:11:21.851  make[1]: Leaving directory '/sonic/src/sonic-sairedis/SAI'
14:11:21.851  dpkg-buildpackage: error: debian/rules build gave error exit status 2
14:11:21.851  [  FAIL LOG END  ] [ target/debs/stretch/libsaithrift-dev_0.9.4_amd64.deb ]

Describe the results you expected:
The build should succeed.

Additional information you deem important (e.g. issue happens only occasionally):
Based on the Jenkins change history for build 448 (when the failures started), this seems to have started after #5651 was merged.

[lguohan]

after building syncd, the current build system will uninstall
libsaibcm-dev package. when building ptf docker, libsaithrift-dev
requires libsaibcm-dev to be installed.

i have a temporary workaround to address this problem in sonic-build-tools.

Azure/sonic-build-tools@8220ed1