use system provided ccache links

Change-Id: I0860bbd0cf368fc3638b861504ebf642ee9d3807
Signed-off-by: Damjan Marion <damarion@cisco.com>

build-root/Makefile

@@ -317,7 +317,8 @@ endif
 
 BUILD_ENV =										\
     export CCACHE_DIR=$(CCACHE_DIR) ;					\
-    export PATH=$(TOOL_INSTALL_DIR)/ccache-bin:$(TOOL_INSTALL_DIR)/bin:$${PATH} ;	\
+    export PATH=$(wildcard /usr/lib*/ccache):$(TOOL_INSTALL_DIR)/bin:$${PATH} ;		\
+    $(if $(call configure_var_fn,PATH), export PATH=$${PATH}:$(call configure_var_fn,PATH);,)	\
     export PATH="`echo $${PATH} | sed -e s/[.]://`" ;					\
     $(if $(not_native),export CONFIG_SITE=$(MU_BUILD_ROOT_DIR)/config.site ;,)	\
     set -eu$(BUILD_DEBUG) ;							        \

build-root/bootstrap.sh

@@ -23,10 +23,7 @@ if [[ ! $CCACHE_DIR ]];then
 fi
 ADD_TO_PATH="$build_root/tools/ccache-bin:$build_root/tools/bin"
 
-# Construct build-config.mk
 cd $build_root
-echo SOURCE_PATH = $wsroot > build-config.mk
-echo 
 echo Saving PATH settings in `pwd`/path_setup
 echo Source this file later, as needed
 cat >path_setup <<EOF
@@ -37,23 +34,13 @@ export CCACHE_DIR=$CCACHE_DIR
 EOF
 
 # regenerate tools/ccache-bin
-rm -rf tools/ccache-bin
-mkdir -p tools/ccache-bin tools/bin
+mkdir -p tools/bin
 
 if [ ! -f /usr/bin/ccache ] ; then
     echo CCACHE is required. Please install it!
     exit 1
 fi
 
-cd tools/ccache-bin
-for c in gcc g++ clang clang++
-do
-    ln -s /usr/bin/ccache $c
-done
-cd ../
-ln -s $wsroot/src/tools/vppapigen/vppapigen  \
-      $build_root/tools/bin/vppapigen
-
 cd $build_root
 
 exit 0

build-root/build-config.mk

@@ -0,0 +1 @@
+SOURCE_PATH = $(CURDIR)/..