Size reduced from 92878 to 91675 bytes.
CMake added CXX files. Removed those.
Removed ceill patch. ceill is not used anymore.
Removed pkgconfig patch. CMake uses a different file, which does not have
this problem.
Further size reduction to 87938 with LTO.
Removed InstallDev. CMAKE_INSTALL takes care of that.
Added WebP support.
Signed-off-by: Rosen Penev <rosenp@gmail.com>