Add Posix build checker to git actions (#489)

* Add Posix build checker to git actions

* fix checker path

* Fix script, checkout recursively

* fix build check script return value

* clone submodules as well with posix checker

* Add quotes to true for submodules

* Fix Submodules

* Remove pcap dependency from Makefile

* install libpcap for build check

* Add networking build to posix

* Separate network build from normal build

* add libpcap after building normal posix

.github/scripts/posix_network_build_checker.sh

@@ -0,0 +1,24 @@
+
+PROJECT=$1
+echo "Verifying url links of: ${PROJECT}"
+if [ ! -d "$PROJECT" ]
+then
+    echo "Directory passed does not exist"
+    exit 2
+fi
+
+SCRIPT_RET=0
+
+set -o nounset        # Treat unset variables as an error
+
+cd ${PROJECT}/FreeRTOS-Plus/Demo/FreeRTOS_Plus_TCP_Echo_Posix
+make
+
+SCRIPT_RET=$?
+
+if [ "${SCRIPT_RET}" -eq 0 ]
+then
+    exit 0
+else
+    exit 1
+fi