Allow re-targeting of naclports install

libraries/SDL-1.2.14/nacl-SDL-1.2.14.sh

Index: libraries/SDL-1.2.14/nacl-SDL-1.2.14.sh
diff --git a/libraries/SDL-1.2.14/nacl-SDL-1.2.14.sh b/libraries/SDL-1.2.14/nacl-SDL-1.2.14.sh
index f41f2f2f62dbe1cde675eb2258dd6d673d61e20a..6600e8983bccfd180570ab565492a0e47d0a0df9 100755
--- a/libraries/SDL-1.2.14/nacl-SDL-1.2.14.sh
+++ b/libraries/SDL-1.2.14/nacl-SDL-1.2.14.sh
@@ -28,8 +28,8 @@ CustomConfigureStep() {
   export AR=${NACLAR}
   export RANLIB=${NACLRANLIB}
   export CFLAGS="-I${NACL_SDK_ROOT}/include"
-  export PKG_CONFIG_PATH=${NACL_SDK_USR_LIB}/pkgconfig
-  export PKG_CONFIG_LIBDIR=${NACL_SDK_USR_LIB}
+  export PKG_CONFIG_PATH=${NACLPORTS_LIBDIR}/pkgconfig
+  export PKG_CONFIG_LIBDIR=${NACLPORTS_LIBDIR}
   export PATH=${NACL_BIN_PATH}:${PATH};
   ChangeDir ${NACL_PACKAGES_REPOSITORY}/${PACKAGE_NAME}
   ./autogen.sh
@@ -48,10 +48,10 @@ CustomConfigureStep() {
     --disable-assembly \
     --disable-pthread-sem \
     --disable-shared \
-    --prefix=${NACL_SDK_USR} \
-    --exec-prefix=${NACL_SDK_USR} \
-    --libdir=${NACL_SDK_USR_LIB} \
-    --oldincludedir=${NACL_SDK_USR_INCLUDE}
+    --prefix=${NACLPORTS_PREFIX} \
+    --exec-prefix=${NACLPORTS_PREFIX} \
+    --libdir=${NACLPORTS_LIBDIR} \
+    --oldincludedir=${NACLPORTS_INCLUDE}
   set +x
 }