patching libbacktrace.mk to build in yocto environment.

Changes include:
Introduced an output folder which will keep all the outputs from the
android-tools.

Adding an include file that is setting the common flags.
Changed the cppflag to include the headers from other components
of android-tools

Modified LDflags so that the libraries that are coming from other android-tools
are searched in the output folder.

Modified the build rule so that it outputs the binary to the OUT_DIR

Signed-off-by: Nisha Parrakat <Nisha.Parrakat@kpit.com>

Upstream-Status: Pending

--- git/system/core/debian/libbacktrace.mk	2021-05-21 23:51:55.022408433 +0000
+++ git/system/core/debian/libbacktrace.mk	2021-05-21 23:53:07.487543521 +0000
@@ -1,5 +1,6 @@
-
-include /usr/share/dpkg/architecture.mk
+include ../../rules_yocto.mk
+#pass architecture specific info to makefile
+DEB_HOST_ARCH=${deb_host_arch}
 
 NAME = libbacktrace
 
@@ -88,11 +89,11 @@
             -Ilibprocinfo/include \
             -Ilibunwindstack/include \
             -I/usr/include/android/lzma \
-            -I/usr/include/android/unwind
+            -I$(OUT_DIR)/usr/include/android/libunwind
 LDFLAGS += -shared -Wl,-soname,$(NAME).so.0 \
            -Wl,-rpath=/usr/lib/$(DEB_HOST_MULTIARCH)/android \
-           -L/usr/lib/$(DEB_HOST_MULTIARCH)/android -lunwind \
-           -L. -lbase -llog -lpthread -l7z
+           -L$(OUT_DIR)/usr/lib/$(DEB_HOST_MULTIARCH)/android -lunwind \
+           -lbase -llog -lpthread -l7z
 
 # -latomic should be the last library specified
 # https://github.com/android/ndk/issues/589
@@ -104,11 +105,11 @@
 endif
 
 build: $(COBJECTS) $(CXXOBJECTS) $(OBJECTS_ASSEMBLY)
-	$(CXX) $^ -o $(NAME).so.0 $(LDFLAGS)
-	ln -s $(NAME).so.0 $(NAME).so
+	$(CXX) $^ -o $(OUT_DIR)/usr/lib/$(DEB_HOST_MULTIARCH)/android/$(NAME).so.0 $(LDFLAGS)
+	ln -s $(OUT_DIR)/usr/lib/$(DEB_HOST_MULTIARCH)/android/$(NAME).so.0 $(NAME).so
 
 clean:
-	$(RM) $(COBJECTS) $(CXXOBJECTS) $(NAME).so*
+	$(RM) $(COBJECTS) $(CXXOBJECTS) $(OUT_DIR)/usr/lib/$(DEB_HOST_MULTIARCH)/android/$(NAME).so*
 
 $(CXXOBJECTS): %.o: %.cpp
 	$(CXX) $< -o $@ $(CXXFLAGS) $(CPPFLAGS)