Fix the intermittent Android-CI build failure.

A few of the docker-containers for Android build environment in Travis may have been wrongly configured recently (have different CPU type than the rest) that the 'native' host tool built from the Android build environment caused illegal instruction (core dumped) when the tool was run on the container host. We are using "ccache" to cache the object files. For this to work, we expect to have a uniform build environments. Setting the deployment target to 'generic' for now in order to workaround the problem.

Source/ThirdParty/LuaJIT/CMakeLists.txt

@@ -395,7 +395,7 @@ if (CMAKE_CROSSCOMPILING)
     set (TOOL_PATH ${CMAKE_CURRENT_BINARY_DIR}/tool/)
     ExternalProject_Add (buildvm
         SOURCE_DIR ${CMAKE_CURRENT_SOURCE_DIR}/src/host
-        CMAKE_ARGS -DURHO3D_64BIT=${URHO3D_64BIT} -DDEST_RUNTIME_DIR=${TOOL_PATH} -DBAKED_CMAKE_SOURCE_DIR=${BAKED_CMAKE_SOURCE_DIR} -DHOST_XCFLAGS=${HOST_XCFLAGS} -DTARGET_ARCH=${TARGET_ARCH} -DDASM_FLAGS=${DASM_FLAGS} -DDASM_ARCH=${DASM_ARCH}
+        CMAKE_ARGS -DURHO3D_64BIT=${URHO3D_64BIT} -DDEST_RUNTIME_DIR=${TOOL_PATH} -DBAKED_CMAKE_SOURCE_DIR=${BAKED_CMAKE_SOURCE_DIR} -DHOST_XCFLAGS=${HOST_XCFLAGS} -DTARGET_ARCH=${TARGET_ARCH} -DDASM_FLAGS=${DASM_FLAGS} -DDASM_ARCH=${DASM_ARCH} -DURHO3D_DEPLOYMENT_TARGET=generic
         ${ALTERNATE_COMMAND})
 else ()
     # Otherwise, build it internally as per normal