libobs-opengl: Make update_buffer data param const

libobs-opengl/gl-helpers.c

@@ -148,7 +148,7 @@ bool gl_create_buffer(GLenum target, GLuint *buffer, GLsizeiptr size,
 	return success;
 }
 
-bool update_buffer(GLenum target, GLuint buffer, void *data, size_t size)
+bool update_buffer(GLenum target, GLuint buffer, const void *data, size_t size)
 {
 	void *ptr;
 	bool success = true;

libobs-opengl/gl-helpers.h

@@ -157,5 +157,5 @@ extern bool gl_copy_texture(struct gs_device *device,
 extern bool gl_create_buffer(GLenum target, GLuint *buffer, GLsizeiptr size,
 		const GLvoid *data, GLenum usage);
 
-extern bool update_buffer(GLenum target, GLuint buffer, void *data,
+extern bool update_buffer(GLenum target, GLuint buffer, const void *data,
 		size_t size);