build: fixed build with latest upstream PX4 Firmware tree

mk/px4_targets.mk

@@ -40,8 +40,11 @@ SKETCHFLAGS=$(SKETCHLIBINCLUDES) -I$(PWD) -DARDUPILOT_BUILD -DCONFIG_HAL_BOARD=H
 
 WARNFLAGS = -Wno-psabi -Wno-packed -Wno-error=double-promotion -Wno-error=unused-variable -Wno-error=unused-but-set-variable -Wno-error=reorder
 
-PX4_MAKE = $(v) make -C $(SKETCHBOOK) -f $(PX4_ROOT)/Makefile EXTRADEFINES="$(SKETCHFLAGS) $(WARNFLAGS) "'$(EXTRAFLAGS)' APM_MODULE_DIR=$(SKETCHBOOK) SKETCHBOOK=$(SKETCHBOOK) PX4_ROOT=$(PX4_ROOT) NUTTX_SRC=$(NUTTX_SRC) MAXOPTIMIZATION="-Os"
-PX4_MAKE_ARCHIVES = make -C $(PX4_ROOT) NUTTX_SRC=$(NUTTX_SRC) archives MAXOPTIMIZATION="-Os"
+# avoid PX4 submodules
+export GIT_SUBMODULES_ARE_EVIL = 1
+
+PX4_MAKE = $(v) GIT_SUBMODULES_ARE_EVIL=1 make -C $(SKETCHBOOK) -f $(PX4_ROOT)/Makefile EXTRADEFINES="$(SKETCHFLAGS) $(WARNFLAGS) "'$(EXTRAFLAGS)' APM_MODULE_DIR=$(SKETCHBOOK) SKETCHBOOK=$(SKETCHBOOK) PX4_ROOT=$(PX4_ROOT) NUTTX_SRC=$(NUTTX_SRC) MAXOPTIMIZATION="-Os" 
+PX4_MAKE_ARCHIVES = make -C $(PX4_ROOT) NUTTX_SRC=$(NUTTX_SRC) archives MAXOPTIMIZATION="-Os" 
 
 .PHONY: module_mk
 module_mk: