[Qt] Removed unused file

Leftover from the gyp -> cmake migration.

platform/qt/scripts/toolchain.sh

@@ -1,21 +0,0 @@
-#!/usr/bin/env bash
-
-set -e
-set -o pipefail
-
-if [ -z ${MASON_SYSROOT:-} ]; then
-    exit 0
-fi
-
-export PATH="`pwd`/.mason:${PATH}"
-export MASON_DIR="`pwd`/.mason"
-
-export PATH=`mason env PATH`
-
-echo CXX=\"`which $(mason env CXX)`\"
-echo CC=\"`which $(mason env CC)`\"
-echo LD=\"`which $(mason env LD)`\"
-echo LINK=\"`which $(mason env CXX)`\"
-echo AR=\"`which $(mason env AR)`\"
-echo RANLIB=\"`which $(mason env RANLIB)`\"
-echo STRIP=\"`which $(mason env STRIP)`\"