clk: sunxi: factors: Add clk cleanup in sunxi_factors_register() error path

sunxi_factors_register() does not check for failures or cleanup after
clk_register_composite() or other clk-related calls.

Signed-off-by: Chen-Yu Tsai <wens@csie.org>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>