clk: davinci: Use the correct size when allocating memory

'sizeof(*pllen)' should be used in place of 'sizeof(*pllout)' to avoid a
small over-allocation.

Fixes: 2d172691

 ("clk: davinci: New driver for davinci PLL clocks")
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Link: https://lore.kernel.org/r/20200809144959.747986-1-christophe.jaillet@wanadoo.fr
Reviewed-by: David Lechner <david@lechnology.com>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>