Use quagga sources as a git submodule (#32)

.gitmodules

@@ -25,3 +25,7 @@
 [submodule "src/p4-hlir/p4-hlir"]
 	path = src/p4-hlir/p4-hlir
 	url = https://github.com/p4lang/p4-hlir
+[submodule "quagga"]
+	path = src/sonic-quagga
+	url = https://github.com/Azure/sonic-quagga
+	branch = debian/0.99.24.1

src/Makefile

@@ -25,9 +25,6 @@ libnl-%.deb:
 libteam5_1.26-1_amd64.deb libteam-dev_1.26-1_amd64.deb libteam-utils_1.26-1_amd64.deb libteamdctl0_1.26-1_amd64.deb: libnl-%.deb
 	pushd libteam; ./build.sh; popd
 
-quagga_0.99.24.1-2_amd64.deb:
-	pushd quagga; ./build.sh; popd
-
 redis-server_3.0.7-2_amd64.deb redis-tools_3.0.7-2_amd64.deb redis-sentinel_3.0.7-2_amd64.deb:
 	pushd redis; ./build.sh; popd
 
@@ -55,6 +52,9 @@ p4-switch_1.0.0_amd64.deb: thrift-compiler_0.9.3-2_amd64.deb python-thrift_0.9.3
 	$(foreach dep, $^, $(call install_deb, $(dep)))
 	pushd p4-switch; ./build.sh; popd
 
+quagga_0.99.24.1-2.1_amd64.deb:
+	$(call build_project, sonic-quagga)
+
 libswsscommon_1.0.0_amd64.deb libswsscommon-dev_1.0.0_amd64.deb: redis-server_3.0.7-2_amd64.deb redis-tools_3.0.7-2_amd64.deb libhiredis0.13_0.13.3-2_amd64.deb libhiredis-dev_0.13.3-2_amd64.deb
 	$(foreach dep, $^, $(call install_deb, $(dep)))
 	$(call build_project, sonic-swss-common)