message: fix pkg-config generation for mingw
diff: @@ -1002,7 +1002,7 @@ endfunction()
  macro(ocv_get_libname var_name)
  get_filename_component(__libname "${ARGN}" NAME)
  # libopencv_core.so.3.3 -> opencv_core
  - string(REGEX REPLACE "^lib(.+)\\.(a|so)(\\.[.0-9]+)?$" "\\1" __libname "${__libname}")
  + string(REGEX REPLACE "^lib(.+)\\.(a|so|dll)(\\.[.0-9]+)?$" "\\1" __libname "${__libname}")
  # MacOSX: libopencv_core.3.3.1.dylib -> opencv_core
  string(REGEX REPLACE "^lib(.+[^.0-9])\\.([.0-9]+\\.)?dylib$" "\\1" __libname "${__libname}")
  set(${var_name} "${__libname}")
  