Issue 6756 - fix build for android-ia32

Makefile

 HOST_ARCH :=$(shell python third_party/detect_v8_host_arch.py)
 
 ifndef HOST_OS
   raw_OS = $(shell uname -s)
   ifeq (${raw_OS},Linux)
     HOST_OS=linux
     TRAVIS_OS_NAME=linux
   else ifeq (${raw_OS},Darwin)
     HOST_OS=mac
     TRAVIS_OS_NAME=osx
   endif
 endif
 
 TARGET_OS ?= ${HOST_OS}
-TARGET_ARCH ?= ${HOST_ARCH}
+ABP_TARGET_ARCH ?= ${HOST_ARCH}
 Configuration ?= debug
 
 # Default V8 directories
 LIBV8_INCLUDE_DIR ?= $(shell pwd -L)/third_party/prebuilt-v8/include
-LIBV8_LIB_DIR ?= $(shell pwd -L)/third_party/prebuilt-v8/${TARGET_OS}-${TARGET_ARCH}-${Configuration}
+LIBV8_LIB_DIR ?= $(shell pwd -L)/third_party/prebuilt-v8/${TARGET_OS}-${ABP_TARGET_ARCH}-${Configuration}
 
 BUILD_DIR ?=$(shell pwd -L)/build
 
 ifeq (${TARGET_OS},android)
 Configuration ?= release
 ANDROID_PLATFORM_LEVEL=android-16
 ANDROID_FIXES=
-ifeq ($(TARGET_ARCH),arm)
+ifeq ($(ABP_TARGET_ARCH),arm)
 ANDROID_ABI = armeabi-v7a
 ANDROID_FIXES="LOCAL_LDFLAGS=\"-Wl,--allow-multiple-definition\""
-else ifeq ($(TARGET_ARCH),ia32)
+else ifeq ($(ABP_TARGET_ARCH),ia32)
 ANDROID_ABI = x86
-else ifeq ($(TARGET_ARCH),arm64)
+else ifeq ($(ABP_TARGET_ARCH),arm64)
 ANDROID_ABI = arm64-v8a
 # minimal platform having arch-arm64, see ndk/platforms
 ANDROID_PLATFORM_LEVEL=android-21
 else
-$(error "Unsupported Android architecture: $(TARGET_ARCH)")
+$(error "Unsupported Android architecture: $(ABP_TARGET_ARCH)")
 endif
 endif
 
 # linux,osx
 #   x64, ia32
 #     debug, release
 # android
 #   arm, arm64, ia32
 #     release
 
-GYP_PARAMETERS=host_arch=${HOST_ARCH} OS=${TARGET_OS} target_arch=${TARGET_ARCH}
+GYP_PARAMETERS=host_arch=${HOST_ARCH} OS=${TARGET_OS} target_arch=${ABP_TARGET_ARCH}
 ifneq "$(and ${LIBV8_LIB_DIR}, ${LIBV8_INCLUDE_DIR})" ""
 GYP_PARAMETERS+= libv8_lib_dir=${LIBV8_LIB_DIR} libv8_include_dir=${LIBV8_INCLUDE_DIR}
 else
 $(error "V8 directories are not specified")
 endif
 
 TEST_EXECUTABLE = ${BUILD_DIR}/out/Debug/tests
 
 .PHONY: all test clean docs ensure_dependencies
 
 .DEFAULT_GOAL:=all
 
 ensure_dependencies:
         python ensure_dependencies.py
 
 test: all
 ifdef FILTER
         $(TEST_EXECUTABLE) --gtest_filter=$(FILTER)
 else
         $(TEST_EXECUTABLE)
 endif
 
 docs:
         doxygen
 
 get-prebuilt-v8:
         URL_PREFIX="https://v8.eyeofiles.com/v8-4fc9a2fe7f8a7ef1e7966185b39b3b541792669a/" \
-        TARGET_OS=${TARGET_OS} TARGET_ARCH=${TARGET_ARCH} \
+        TARGET_OS=${TARGET_OS} ABP_TARGET_ARCH=${ABP_TARGET_ARCH} \
         TRAVIS_OS_NAME=${TRAVIS_OS_NAME} Configuration=${Configuration} \
         bash .travis/prepare-prebuilt-v8.sh
 
 clean:
         $(RM) -r ${BUILD_DIR} docs
 
 ifeq ($(TARGET_OS),android)
 SUB_ACTION ?= installed_modules
 all: ensure_dependencies
         GYP_DEFINES="${GYP_PARAMETERS}" \
         python ./make_gyp_wrapper.py --depth=. -f make-android -Ilibadblockplus.gypi --generator-output=${BUILD_DIR} -Gandroid_ndk_version=r16b libadblockplus.gyp
         $(ANDROID_NDK_ROOT)/ndk-build -C ${BUILD_DIR} ${SUB_ACTION} \
         BUILDTYPE=Release \
         APP_ABI=$(ANDROID_ABI) \
         APP_PLATFORM=${ANDROID_PLATFORM_LEVEL} \
         APP_PIE=true \
         APP_STL=c++_shared \
         APP_BUILD_SCRIPT=Makefile \
         NDK_PROJECT_PATH=. \
         NDK_OUT=. \
         ${ANDROID_FIXES} \
-        NDK_APP_DST_DIR=android-$(TARGET_ARCH).release
+        NDK_APP_DST_DIR=android-$(ABP_TARGET_ARCH).release
 else
 SUB_ACTION ?= all
 all: ensure_dependencies 
         GYP_DEFINES="${GYP_PARAMETERS}" third_party/gyp/gyp --depth=. -f make -I libadblockplus.gypi --generator-output=${BUILD_DIR} libadblockplus.gyp
         $(MAKE) -C ${BUILD_DIR} ${SUB_ACTION}
 
 endif