Linux to posix conversion

Changed "linux" target to "posix". Most of the changes are shared with
QuRT and with OSX. The Linux specific parts are in for i2c which uses
<linux/i2c.h> and <linux/i2c-dev.h>.

There is also a check for __PX4_LINUX in mavlink for a tty ioctl that is
not supported.

Signed-off-by: Mark Charlebois <charlebm@gmail.com>

makefiles/nuttx/board_px4-stm32f4discovery.mk

@@ -0,0 +1,11 @@
+#
+# Board-specific definitions for the PX4_STM32F4DISCOVERY
+#
+
+#
+# Configure the toolchain
+#
+CONFIG_ARCH			 = CORTEXM4F
+CONFIG_BOARD			 = PX4_STM32F4DISCOVERY
+
+include $(PX4_MK_DIR)/toolchain_gnu-arm-eabi.mk

makefiles/nuttx/config_px4-stm32f4discovery_default.mk

@@ -0,0 +1,92 @@
+#
+# Makefile for the px4fmu_default configuration
+#
+
+#
+# Use the configuration's ROMFS, copy the PX4_STM32F4DISCOVERY firmware into
+# the ROMFS if it's available
+#
+ROMFS_ROOT	 = $(PX4_BASE)/ROMFS/px4fmu_common
+ROMFS_OPTIONAL_FILES = 
+
+#
+# Board support modules
+#
+MODULES		+= drivers/device
+MODULES		+= drivers/stm32
+MODULES		+= drivers/led
+MODULES		+= drivers/boards/px4-stm32f4discovery
+
+#
+# System commands
+#
+MODULES		+= systemcmds/bl_update
+MODULES		+= systemcmds/mixer
+MODULES		+= systemcmds/param
+MODULES		+= systemcmds/perf
+MODULES		+= systemcmds/reboot
+MODULES		+= systemcmds/top
+MODULES		+= systemcmds/tests
+MODULES		+= systemcmds/config
+MODULES		+= systemcmds/nshterm
+MODULES		+= systemcmds/ver
+
+#
+# Library modules
+#
+MODULES		+= modules/systemlib
+MODULES		+= modules/systemlib/mixer
+MODULES		+= modules/controllib
+MODULES		+= modules/uORB
+
+#
+# Libraries
+#
+LIBRARIES	+= lib/mathlib/CMSIS
+MODULES		+= lib/mathlib
+MODULES		+= lib/mathlib/math/filter
+MODULES		+= lib/ecl
+MODULES		+= lib/external_lgpl
+MODULES		+= lib/geo
+MODULES		+= lib/conversion
+MODULES		+= platforms/nuttx
+
+#
+# Demo apps
+#
+#MODULES		+= examples/math_demo
+# Tutorial code from
+# https://pixhawk.ethz.ch/px4/dev/hello_sky
+MODULES		+= examples/px4_simple_app
+
+# Tutorial code from
+# https://pixhawk.ethz.ch/px4/dev/daemon
+#MODULES		+= examples/px4_daemon_app
+
+# Tutorial code from
+# https://pixhawk.ethz.ch/px4/dev/debug_values
+#MODULES		+= examples/px4_mavlink_debug
+
+# Tutorial code from
+# https://pixhawk.ethz.ch/px4/dev/example_fixedwing_control
+#MODULES			+= examples/fixedwing_control
+
+# Hardware test
+#MODULES			+= examples/hwtest
+
+#
+# Transitional support - add commands from the NuttX export archive.
+#
+# In general, these should move to modules over time.
+#
+# Each entry here is <command>.<priority>.<stacksize>.<entrypoint> but we use a helper macro
+# to make the table a bit more readable.
+#
+define _B
+	$(strip $1).$(or $(strip $2),SCHED_PRIORITY_DEFAULT).$(or $(strip $3),CONFIG_PTHREAD_STACK_DEFAULT).$(strip $4)
+endef
+
+#                  command                 priority                   stack  entrypoint
+BUILTIN_COMMANDS := \
+	$(call _B, sercon,                 ,                          2048,  sercon_main                ) \
+	$(call _B, serdis,                 ,                          2048,  serdis_main                )

makefiles/nuttx/gumstix-aerocore.cfg

@@ -0,0 +1,10 @@
+# JTAG for the STM32F4x chip used on the Gumstix AeroCore is available on
+# the first interface of a Quad FTDI chip.  nTRST is bit 4.
+interface ftdi
+ftdi_vid_pid 0x0403 0x6011
+
+ftdi_layout_init 0x0000 0x001b
+ftdi_layout_signal nTRST -data 0x0010
+
+source [find target/stm32f4x.cfg]
+reset_config trst_only