cmake: handle VIDEOIO_PLUGIN_LIST=all

modules/videoio/CMakeLists.txt

@@ -1,4 +1,4 @@
-set(VIDEOIO_PLUGIN_LIST "" CACHE STRING "List of videoio backends to be compiled as plugins (ffmpeg, gstreamer)")
+set(VIDEOIO_PLUGIN_LIST "" CACHE STRING "List of videoio backends to be compiled as plugins (ffmpeg, gstreamer, mfx, msmf or special value 'all')")
 set(VIDEOIO_ENABLE_PLUGINS "ON" CACHE BOOL "Allow building videoio plugin support")
 set(VIDEOIO_ENABLE_STRICT_PLUGIN_CHECK "ON" CACHE BOOL "Make sure OpenCV version is the same in plugin and host code")
 mark_as_advanced(VIDEOIO_PLUGIN_LIST VIDEOIO_ENABLE_PLUGINS VIDEOIO_ENABLE_STRICT_PLUGIN_CHECK)
@@ -69,7 +69,7 @@ include(${CMAKE_CURRENT_LIST_DIR}/cmake/plugin.cmake)
 set(tgts)
 
 if(TARGET ocv.3rdparty.mediasdk)
-  if("mfx" IN_LIST VIDEOIO_PLUGIN_LIST)
+  if("mfx" IN_LIST VIDEOIO_PLUGIN_LIST OR VIDEOIO_PLUGIN_LIST STREQUAL "all")
     ocv_create_builtin_videoio_plugin("opencv_videoio_intel_mfx" ocv.3rdparty.mediasdk "cap_mfx_common.cpp" "cap_mfx_reader.cpp" "cap_mfx_writer.cpp" "cap_mfx_plugin.cpp")
   else()
     list(APPEND videoio_srcs
@@ -91,7 +91,7 @@ if(TARGET ocv.3rdparty.dshow)
 endif()
 
 if(TARGET ocv.3rdparty.msmf)
-  if("msmf" IN_LIST VIDEOIO_PLUGIN_LIST)
+  if("msmf" IN_LIST VIDEOIO_PLUGIN_LIST OR VIDEOIO_PLUGIN_LIST STREQUAL "all")
     ocv_create_builtin_videoio_plugin("opencv_videoio_msmf" ocv.3rdparty.msmf "cap_msmf.cpp")
   else()
     list(APPEND videoio_srcs ${CMAKE_CURRENT_LIST_DIR}/src/cap_msmf.hpp)
@@ -111,7 +111,7 @@ if(TARGET ocv.3rdparty.dc1394_2)
 endif()
 
 if(TARGET ocv.3rdparty.gstreamer)
-  if("gstreamer" IN_LIST VIDEOIO_PLUGIN_LIST)
+  if("gstreamer" IN_LIST VIDEOIO_PLUGIN_LIST OR VIDEOIO_PLUGIN_LIST STREQUAL "all")
     ocv_create_builtin_videoio_plugin("opencv_videoio_gstreamer" ocv.3rdparty.gstreamer "cap_gstreamer.cpp")
   else()
     list(APPEND videoio_srcs ${CMAKE_CURRENT_LIST_DIR}/src/cap_gstreamer.cpp)
@@ -137,7 +137,7 @@ endif()
 if(TARGET ocv.3rdparty.ffmpeg)
   if(HAVE_FFMPEG_WRAPPER)
     list(APPEND tgts ocv.3rdparty.ffmpeg)
-  elseif("ffmpeg" IN_LIST VIDEOIO_PLUGIN_LIST)
+  elseif("ffmpeg" IN_LIST VIDEOIO_PLUGIN_LIST OR VIDEOIO_PLUGIN_LIST STREQUAL "all")
     ocv_create_builtin_videoio_plugin("opencv_videoio_ffmpeg" ocv.3rdparty.ffmpeg "cap_ffmpeg.cpp")
   else()
     list(APPEND videoio_hdrs ${CMAKE_CURRENT_LIST_DIR}/src/cap_ffmpeg_impl.hpp)