Set PKG_CONFIG_PATH in build-cpython

Author: zanieb

cpython-unix/build-cpython.sh

@@ -8,6 +8,7 @@ set -ex
 export ROOT=`pwd`
 
 export PATH=${TOOLS_PATH}/${TOOLCHAIN}/bin:${TOOLS_PATH}/host/bin:${TOOLS_PATH}/deps/bin:$PATH
+export PKG_CONFIG_PATH=${TOOLS_PATH}/deps/share/pkgconfig:${TOOLS_PATH}/deps/lib/pkgconfig
 
 # configure somehow has problems locating llvm-profdata even though it is in
 # PATH. The macro it is using allows us to specify its path via an