message: Simplify implementation of MESHOPT_BUILD_SHARED_LIBS
  Instead of overwriting builtin BUILD_SHARED_LIBS option we can simply
  change the type of the meshoptimizer library, which is cleaner.
diff: @@ -15,11 +15,6 @@ option(MESHOPT_BUILD_DEMO "Build demo" OFF)
  option(MESHOPT_BUILD_GLTFPACK "Build gltfpack" OFF)
  option(MESHOPT_BUILD_SHARED_LIBS "Build shared libraries" OFF)
  -# add_library() needs BUILD_SHARED_LIBS set to decide between static and
  -# shared. This also sets it back to OFF in case parent project has
  -# BUILD_SHARED_LIBS but wants MESHOPT_BUILD_SHARED_LIBS to be OFF.
  -set(BUILD_SHARED_LIBS ${MESHOPT_BUILD_SHARED_LIBS})
  -
  set(SOURCES
  src/meshoptimizer.h
  src/allocator.cpp
  @@ -61,7 +56,12 @@ else()
  add_compile_options(-Wall -Wextra -Wshadow -Wno-missing-field-initializers -Werror)
  endif()
  -add_library(meshoptimizer ${SOURCES})
  +if(MESHOPT_BUILD_SHARED_LIBS)
  + add_library(meshoptimizer SHARED ${SOURCES})
  +else()
  + add_library(meshoptimizer STATIC ${SOURCES})
  +endif()
  +
  target_include_directories(meshoptimizer INTERFACE "$<BUILD_INTERFACE:${CMAKE_CURRENT_SOURCE_DIR}/src>")
  if(MESHOPT_BUILD_SHARED_LIBS)
  