rebuild.sh: Fix PKG_CONFIG definition.

scripts/rebuild.sh

diff --git a/scripts/rebuild.sh b/scripts/rebuild.sh
index 84a7546..eeb072f 100755
--- a/scripts/rebuild.sh
+++ b/scripts/rebuild.sh
@@ -146,7 +146,6 @@
 ORIGINAL_PATH=$PATH
 
 export PKG_CONFIG=$(which pkg-config 2>/dev/null)
-PKG_CONFIG=
 if [ "$PKG_CONFIG" ]; then
     log "Found pkg-config at: $PKG_CONFIG"
 else