fix[build]: Avoid exporting toolchain to system PATH

Change-Id: Ic85b4a20df81d4a430ca9563d3555e38cfe97338
Signed-off-by: Johnson Ding <johnson.ding@rock-chips.com>

build/linux/arm/make-Makefiles.bash

@@ -5,21 +5,30 @@ set +e
 
 MPP_PWD=`pwd`
 MPP_TOP=${MPP_PWD}/../../..
+DEFAULT_TOOLCHAIN=arm-linux-gnueabi-
 
 # toolchain detection
 check_cmd(){
     "$@" >> /dev/null 2>&1
 }
-check_system_arm_linux_gcc(){
-    check_cmd arm-linux-gcc -v
+check_gcc(){
+    check_cmd ${TOOLCHAIN}gcc -v
 }
 
 source ../opt_proc.sh
 
-check_system_arm_linux_gcc
+if [ -z "${TOOLCHAIN}" ]; then
+    echo "Using system ${DEFAULT_TOOLCHAIN} as toolchain."
+    TOOLCHAIN=$DEFAULT_TOOLCHAIN
+fi
+
+check_gcc
+
 if [ $? -eq 127 ];then
-    MPP_TOOLCHAIN=${MPP_TOP}/../prebuilts/toolschain/usr/bin
-    export PATH=$PATH:${MPP_TOOLCHAIN}
+    echo -e "\e[31m${TOOLCHAIN}gcc is not found!\e[0m"
+    echo -e "Please specify valid toolchain path and it's prefix to variable 'TOOLCHAIN' with argument --toolchain."
+    echo -e "For example:\n \t./make-Makefiles.bin --toolchain /path-to-toolchain/arm-linux-gnueabi-"
+    exit 1
 fi
 
 # generate Makefile