media: s5p-mfc: Fix encoder menu controls initialization
This patch fixes the menu_skip_mask field initialization and
addresses a following issue found by the SVACE static analysis:
* NO_EFFECT.SELF: assignment to self in expression 'cfg.menu_skip_mask = cfg.menu_skip_mask'
No effect at drivers/media/platform/s5p-mfc/s5p_mfc_enc.c:2083