restoring/saving coprocessor state. These function don't use call8 or call12 and thus need to create just 16 bytes for the base save area, however they do use one variable so we need a space for that. The `entry` instruction works in unit of 8 bytes so we add whole 8 bytes for one variable. Signed-off-by: Abdelatif Guettouche <abdelatif.guettouche@espressif.com>