ut: add unit test build infrastructure

New build targets:
  make ut_all
  make ut_clean

to build (or clean) all unit tests.

make/unittest.mk

@@ -0,0 +1,43 @@
+###############################################################################
+# @file       unittest.mk
+# @author     PhoenixPilot, http://github.com/PhoenixPilot, Copyright (C) 2012
+# @addtogroup 
+# @{
+# @addtogroup 
+# @{
+# @brief Makefile template for unit tests
+###############################################################################
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful, but
+# WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+# or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+# for more details.
+#
+# You should have received a copy of the GNU General Public License along
+# with this program; if not, write to the Free Software Foundation, Inc.,
+# 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+#
+
+# Need to disable THUMB mode for unit tests
+override THUMB :=
+
+EXTRAINCDIRS    += .
+ALLSRC          := $(SRC) $(wildcard ./*.c)
+ALLSRCBASE      := $(notdir $(basename $(ALLSRC)))
+ALLOBJ          := $(addprefix $(OUTDIR)/, $(addsuffix .o, $(ALLSRCBASE)))
+
+.PHONY: $(TARGET)
+$(TARGET): | $(OUTDIR)
+$(TARGET): $(OUTDIR)/$(TARGET).elf
+
+$(OUTDIR):
+	$(V1) mkdir -p $@
+
+$(foreach src,$(ALLSRC),$(eval $(call COMPILE_C_TEMPLATE,$(src))))
+$(eval $(call LINK_TEMPLATE,$(OUTDIR)/$(TARGET).elf,$(ALLOBJ)))
+