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/posix/board_posix.mk

@@ -0,0 +1,11 @@
+#
+# Board-specific definitions for the POSIX port of PX4
+#
+
+#
+# Configure the toolchain
+#
+CONFIG_ARCH			 = NATIVE
+CONFIG_BOARD			 = POSIXTEST
+
+include $(PX4_MK_DIR)/toolchain_native.mk

makefiles/posix/config_posix_default.mk

@@ -0,0 +1,72 @@
+#
+# Makefile for the POSIXTEST *default* configuration
+#
+
+#
+# Board support modules
+#
+MODULES		+= drivers/device
+MODULES		+= drivers/blinkm
+MODULES		+= drivers/hil
+MODULES		+= drivers/rgbled
+MODULES		+= modules/sensors
+#MODULES		+= drivers/ms5611
+
+#
+# System commands
+#
+MODULES	+= systemcmds/param
+
+#
+# General system control
+#
+MODULES		+= modules/mavlink
+
+#
+# Estimation modules (EKF/ SO3 / other filters)
+#
+MODULES		+= modules/attitude_estimator_ekf
+MODULES		+= modules/ekf_att_pos_estimator
+
+#
+# Vehicle Control
+#
+MODULES		+= modules/mc_att_control
+
+#
+# Library modules
+#
+MODULES		+= modules/systemlib
+MODULES		+= modules/systemlib/mixer
+MODULES		+= modules/uORB
+MODULES		+= modules/dataman
+MODULES		+= modules/sdlog2
+MODULES		+= modules/simulator
+MODULES		+= modules/commander
+
+#
+# Libraries
+#
+MODULES		+= lib/mathlib
+MODULES		+= lib/mathlib/math/filter
+MODULES		+= lib/geo
+MODULES		+= lib/geo_lookup
+MODULES		+= lib/conversion
+
+#
+# Linux port
+#
+MODULES		+= platforms/posix/px4_layer
+MODULES		+= platforms/posix/drivers/accelsim
+MODULES		+= platforms/posix/drivers/gyrosim
+MODULES		+= platforms/posix/drivers/adcsim
+MODULES		+= platforms/posix/drivers/barosim
+
+#
+# Unit tests
+#
+#MODULES		+= platforms/posix/tests/hello
+#MODULES		+= platforms/posix/tests/vcdev_test
+#MODULES		+= platforms/posix/tests/hrt_test
+#MODULES		+= platforms/posix/tests/wqueue
+