ArduPilot: removed unusued submodules

Author: tridge

.gitmodules

@@ -1,9 +1,6 @@
 [submodule "mavlink/include/mavlink/v1.0"]
 	path = mavlink/include/mavlink/v1.0
 	url = git://github.com/mavlink/c_library.git
-[submodule "NuttX"]
-	path = NuttX
-	url = git://github.com/PX4/NuttX.git
 [submodule "src/modules/uavcan/libuavcan"]
 	path = src/modules/uavcan/libuavcan
 	url = git://github.com/UAVCAN/libuavcan.git
@@ -13,16 +10,6 @@
 [submodule "Tools/gencpp"]
 	path = Tools/gencpp
 	url = https://github.com/ros/gencpp.git
-[submodule "Tools/jMAVSim"]
-	path = Tools/jMAVSim
-	url = https://github.com/PX4/jMAVSim.git
-[submodule "Tools/sitl_gazebo"]
-	path = Tools/sitl_gazebo
-	url = https://github.com/PX4/sitl_gazebo.git
-[submodule "unittests/googletest"]
-	path = unittests/googletest
-	url = https://github.com/google/googletest.git
-	ignore = untracked
 [submodule "src/lib/matrix"]
 	path = src/lib/matrix
 	url = https://github.com/PX4/Matrix.git
@@ -32,6 +19,3 @@
 [submodule "src/lib/ecl"]
 	path = src/lib/ecl
 	url = https://github.com/PX4/ecl.git
-[submodule "cmake/cmake_hexagon"]
-	path = cmake/cmake_hexagon
-	url = https://github.com/ATLFlight/cmake_hexagon