Fix search path for qmlplugindump tool

CMake kept picking up the binary from /usr/bin which belongs to Qt4 installation.
Here we require CMake to use the binary from Qt5 installation that is being used.

Author: wonder-sk

cmake/FindQtQmlTools.cmake

@@ -1,12 +1,12 @@
 # Qt QML Tools
 # ~~~~~~~~~~~~
-# 
+#
 # To generate qmltypes files required by Qt Creator to allow QML code inspection
 # (http://doc.qt.io/qtcreator/creator-qml-modules-with-plugins.html#generating-qmltypes-files)
 # we need to have installed qmlplugindump unity (shipped with Qt 4.8 and later)
 # http://doc.qt.io/qtcreator/creator-qml-modules-with-plugins.html#dumping-plugins-automatically
 #
-# Find the installed version of qmlplugindump utility. 
+# Find the installed version of qmlplugindump utility.
 # FindQtQmlTools should be called after Qt5 has been found
 #
 # This file defines the following variables:
@@ -15,20 +15,22 @@
 # QMLPLUGINDUMP_EXECUTABLE - Path to qmlplugindump executable
 #
 # Also defines MACRO to create qmltypes file, when QML directory is supplied
-# 
+#
 # Copyright (c) 2017, Peter Petrik <zilolv at gmail dot com>
 # Redistribution and use is allowed according to the terms of the BSD license.
 # For details see the accompanying COPYING-CMAKE-SCRIPTS file.
 
 MACRO(FIND_QMLPLUGINDUMP)
+  get_filename_component(QT_BIN_DIR "${QT_QMAKE_EXECUTABLE}" DIRECTORY)
+
   IF(NOT QMLPLUGINDUMP_EXECUTABLE)
     IF (MSVC)
-      FIND_PROGRAM(QMLPLUGINDUMP_EXECUTABLE qmlplugindump.exe)
+      FIND_PROGRAM(QMLPLUGINDUMP_EXECUTABLE qmlplugindump.exe PATHS ${QT_BIN_DIR} NO_DEFAULT_PATH)
     ELSE (MSVC)
-      FIND_PROGRAM(QMLPLUGINDUMP_EXECUTABLE qmlplugindump)
+      FIND_PROGRAM(QMLPLUGINDUMP_EXECUTABLE qmlplugindump PATHS ${QT_BIN_DIR} NO_DEFAULT_PATH)
     ENDIF (MSVC)
   ENDIF(NOT QMLPLUGINDUMP_EXECUTABLE)
-  
+
   IF (QMLPLUGINDUMP_EXECUTABLE)
     SET(QMLPLUGINDUMP_FOUND TRUE)
     MESSAGE(STATUS "Found qmlplugindump: ${QMLPLUGINDUMP_EXECUTABLE}")