Added host-building mixer test

Tools/tests-host/.gitignore

+./obj/*
+mixer_test

Tools/tests-host/Makefile

+
+CC=g++
+CFLAGS=-I. -I../../src/modules -I ../../src/include -I../../src/drivers -I../../src -D__EXPORT="" -Dnullptr="0"
+
+ODIR=obj
+LDIR =../lib
+
+LIBS=-lm
+
+#_DEPS = test.h
+#DEPS = $(patsubst %,$(IDIR)/%,$(_DEPS))
+
+_OBJ = mixer_test.o test_mixer.o mixer_simple.o mixer_multirotor.o mixer.o mixer_group.o
+OBJ = $(patsubst %,$(ODIR)/%,$(_OBJ))
+
+#$(DEPS)
+$(ODIR)/%.o: %.cpp
+	$(CC) -c -o $@ $< $(CFLAGS)
+
+$(ODIR)/%.o: ../../src/systemcmds/tests/%.c
+	$(CC) -c -o $@ $< $(CFLAGS)
+
+$(ODIR)/%.o: ../../src/modules/systemlib/%.cpp
+	$(CC) -c -o $@ $< $(CFLAGS)
+
+$(ODIR)/%.o: ../../src/modules/systemlib/mixer/%.cpp
+	$(CC) -c -o $@ $< $(CFLAGS)
+
+#
+mixer_test: $(OBJ)
+	g++ -o $@ $^ $(CFLAGS) $(LIBS)
+
+.PHONY: clean
+
+clean:
+	rm -f $(ODIR)/*.o *~ core $(INCDIR)/*~
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Tools/tests-host/mixer_test.cpp

+#include <systemlib/mixer/mixer.h>
+#include <systemlib/err.h>
+
+extern int test_mixer(int argc, char *argv[]);
+
+int main(int argc, char *argv[]) {
+	warnx("Host execution started");
+
+	char* args[] = {argv[0], "../../ROMFS/px4fmu_common/mixers/IO_pass.mix"};
+
+	test_mixer(2, args);
+}
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