opencv: always enable opencv_core module when opencv is enabled

It does not make much sense enabling opencv without its core module.

This configuration leads to build nothing (since all modules depend on
the core one), but install the configuration files (*.pc and *.cmake)
anyway.

This absurd situation may break the build-system of other packages
that would correctly find the *.pc (but does not check for the modules
they actually use), but would not build because of missing headers and
libraries.

Signed-off-by: Samuel Martin <s.martin49@gmail.com>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>

package/opencv/Config.in

@@ -26,12 +26,6 @@ config BR2_PACKAGE_OPENCV_LIB_CONTRIB
 	help
 	  Include opencv_contrib module into the OpenCV build.
 
-config BR2_PACKAGE_OPENCV_LIB_CORE
-	bool "core"
-	default y
-	help
-	  Include opencv_core module into the OpenCV build.
-
 config BR2_PACKAGE_OPENCV_LIB_FEATURES2D
 	bool "features2d"
 	default y

package/opencv/opencv.mk

@@ -34,7 +34,7 @@ OPENCV_CONF_OPT += \
 	-DBUILD_opencv_androidcamera=OFF                                        \
 	-DBUILD_opencv_calib3d=$(if $(BR2_PACKAGE_OPENCV_LIB_CALIB3D),ON,OFF)   \
 	-DBUILD_opencv_contrib=$(if $(BR2_PACKAGE_OPENCV_LIB_CONTRIB),ON,OFF)   \
-	-DBUILD_opencv_core=$(if $(BR2_PACKAGE_OPENCV_LIB_CORE),ON,OFF)         \
+	-DBUILD_opencv_core=ON                                                  \
 	-DBUILD_opencv_features2d=$(if $(BR2_PACKAGE_OPENCV_LIB_FEATURES2D),ON,OFF) \
 	-DBUILD_opencv_flann=$(if $(BR2_PACKAGE_OPENCV_LIB_FLANN),ON,OFF)       \
 	-DBUILD_opencv_gpu=$(if $(BR2_PACKAGE_OPENCV_LIB_GPU),ON,OFF)           \