Add code to copy cursor image to opengl texture and update on event update (not used yet)

src/egl.c

@@ -138,6 +138,7 @@ static bool gsr_egl_load_gl(gsr_egl *self, void *library) {
         { (void**)&self->glTexImage2D, "glTexImage2D" },
         { (void**)&self->glCopyImageSubData, "glCopyImageSubData" },
         { (void**)&self->glClearTexImage, "glClearTexImage" },
+        { (void**)&self->glGenerateMipmap, "glGenerateMipmap" },
         { (void**)&self->glGenFramebuffers, "glGenFramebuffers" },
         { (void**)&self->glBindFramebuffer, "glBindFramebuffer" },
         { (void**)&self->glDeleteFramebuffers, "glDeleteFramebuffers" },