abicheck: use absoute path for build too

abicheck/apt_build.xml

@@ -3,9 +3,9 @@
 </version>
    
  <headers>
-  ../build/include/apt-pkg
+  @build_path@/include/apt-pkg
  </headers>
    
  <libs>
-  ../build/bin/
+  @build_path@/bin/
  </libs>

abicheck/run_abi_test

@@ -8,4 +8,7 @@ fi
 LIBPATH=$(find /usr/lib/ -type f  -name "libapt-pkg*")
 sed s#@installed_libapt@#$LIBPATH# apt_installed.xml.in > apt_installed.xml
 
+BUILDPATH=$(readlink -f ../build)
+sed s#@build_path@#$BUILDPATH# apt_build.xml.in > apt_build.xml
+
 perl abi-compliance-checker.pl -l apt -d1 apt_installed.xml -d2 apt_build.xml