go: Call 'heif_context_read_from_memory_without_copy' instead of depr…

…ecated function

heif.c:319 says:
    // DEPRECATED: use heif_context_read_from_memory_without_copy() instead.

go/heif/heif.go

@@ -321,7 +321,7 @@ func (c *Context) ReadFromFile(filename string) error {
 
 func (c *Context) ReadFromMemory(data []byte) error {
  // TODO: Use reader API internally.
- err := C.heif_context_read_from_memory(c.context, unsafe.Pointer(&data[0]), C.size_t(len(data)), nil)
+ err := C.heif_context_read_from_memory_without_copy(c.context, unsafe.Pointer(&data[0]), C.size_t(len(data)), nil)
  return convertHeifError(err)
 }