patching fastboot.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/fastboot.mk	2021-05-17 07:47:56.800224043 +0000
+++ git/system/core/debian/fastboot.mk	2021-05-17 07:49:40.130383096 +0000
@@ -1,3 +1,4 @@
+include ../../rules_yocto.mk
 NAME = fastboot
 fastboot_SOURCES = \
           bootimg_utils.cpp \
@@ -38,11 +39,11 @@
             -Ifs_mgr/liblp/include \
             -I/usr/include/android/openssl \
             -Ilibsparse/include \
-            -Ilibziparchive/include
+            -Ilibziparchive/include -I$(OUT_DIR)/usr/include/ 
 LDFLAGS += -Wl,-rpath=/usr/lib/$(DEB_HOST_MULTIARCH)/android \
            -fuse-ld=gold \
-           -Wl,-rpath-link=. \
-           -L. -lziparchive -lsparse -lbase -lcutils -ladb -lcrypto -lext4_utils \
+           -Wl,-rpath-link=$(OUT_DIR)/usr/lib/$(DEB_HOST_MULTIARCH)/android \
+           -L$(OUT_DIR)/usr/lib/$(DEB_HOST_MULTIARCH)/android -lziparchive -lsparse -lbase -lcutils -ladb -lcrypto -lext4_utils \
            -L/usr/lib/$(DEB_HOST_MULTIARCH)/android \
            -l7z \
 
@@ -53,7 +54,8 @@
 endif
 
 build: $(SOURCES)
-	$(CXX) $^ -o fastboot/$(NAME) $(CXXFLAGS) $(CPPFLAGS) $(LDFLAGS)
+	mkdir --parents $(OUT_DIR)/usr/bin/fastboot
+	$(CXX) $^ -o $(OUT_DIR)/usr/bin/fastboot/$(NAME) $(CXXFLAGS) $(CPPFLAGS) $(LDFLAGS)
 
 clean:
-	$(RM) fastboot/$(NAME)
+	$(RM) $(OUT_DIR)/usr/bin/fastboot/$(NAME)