Fix pkg-config generation

Replace absolute library path with library name spec and library search
path option.

The fix has been provided by Ray Rashif (code.opencv.org/issues/1925)

Upstream-Status: Pending

diff -Nbaur OpenCV-2.4.3.orig/cmake/OpenCVGenPkgconfig.cmake OpenCV-2.4.3/cmake/OpenCVGenPkgconfig.cmake
--- OpenCV-2.4.3.orig/cmake/OpenCVGenPkgconfig.cmake	2012-11-04 08:40:14.243505926 +0000
+++ OpenCV-2.4.3/cmake/OpenCVGenPkgconfig.cmake	2012-11-04 08:40:42.286649120 +0000
@@ -10,7 +10,7 @@
 # -------------------------------------------------------------------------------------------
 set(prefix      "${CMAKE_INSTALL_PREFIX}")
 set(exec_prefix "\${prefix}")
-set(libdir      "") #TODO: need link paths for OpenCV_EXTRA_COMPONENTS
+set(libdir      "\${prefix}/${OPENCV_LIB_INSTALL_PATH}")
 set(includedir  "\${prefix}/${OPENCV_INCLUDE_INSTALL_PATH}")
 set(VERSION     ${OPENCV_VERSION})
 
@@ -36,10 +36,11 @@
 ocv_list_reverse(OpenCV_EXTRA_COMPONENTS)
 
 #build the list of components
-set(OpenCV_LIB_COMPONENTS_ "")
+set(OpenCV_LIB_COMPONENTS_ "-L\${libdir}")
 foreach(CVLib ${OpenCV_LIB_COMPONENTS})
   get_target_property(libpath ${CVLib} LOCATION_${CMAKE_BUILD_TYPE})
   get_filename_component(libname "${libpath}" NAME)
+  get_filename_component(lname "${libpath}" NAME_WE)
 
   if(INSTALL_TO_MANGLED_PATHS)
     set(libname "${libname}.${OPENCV_VERSION}")
@@ -52,7 +53,8 @@
     set(installDir "${OPENCV_LIB_INSTALL_PATH}")
   endif()
 
-  set(OpenCV_LIB_COMPONENTS_ "${OpenCV_LIB_COMPONENTS_} \${exec_prefix}/${installDir}/${libname}")
+  string(REPLACE "libopencv" "-lopencv" lname "${lname}")
+  set(OpenCV_LIB_COMPONENTS_ "${OpenCV_LIB_COMPONENTS_} ${lname}")
 endforeach()
 
 # add extra dependencies required for OpenCV