scripts: unset CDPATH if cd is used

This wonderful/awful little bash shell variable wrecks havoc on `cd`
calls in shell scripts. Unset CDPATH in makepkg where we use `cd` quite
heavily. In pacman-optimize, we can move the change directory logic into
the bsdtar call so we are left with no usages of `cd` in the script.

Signed-off-by: Dan McGee <dan@archlinux.org>

scripts/makepkg.sh.in

@@ -36,6 +36,8 @@ export TEXTDOMAINDIR='@localedir@'
 
 # file -i does not work on Mac OSX unless legacy mode is set
 export COMMAND_MODE='legacy'
+# Ensure CDPATH doesn't screw with our cd calls
+unset CDPATH
 
 myver='@PACKAGE_VERSION@'
 confdir='@sysconfdir@'

scripts/pacman-optimize.sh.in

@@ -122,8 +122,7 @@ find "$dbroot" -type f | sort | xargs md5sum > "$workdir/pacsums.old"
 
 # step 2: tar it up
 msg "$(gettext "Tar'ing up %s...")" "$dbroot"
-cd "$dbroot"
-bsdtar -czf "$workdir/pacman-db.tar.gz" ./
+bsdtar -czf "$workdir/pacman-db.tar.gz" -C "$dbroot" ./
 if (( $? )); then
 	rm -rf "$workdir"
 	die_r "$(gettext "Tar'ing up %s failed.")" "$dbroot"