Input: spear-keyboard - switch to devm_clk_get_prepared()

Input: spear-keyboard - switch to devm_clk_get_prepared()

Use devm_clk_get_prepared() in order to remove a clk_unprepare() in an
error handling path of the probe and from the .remove() function.

This done, the whole .remove() function can also be axed because
'input_dev' is a managed resource allocated with
devm_input_allocate_device() and we can fully rely on devm for cleaning up.

Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Link: https://lore.kernel.org/r/062986b0a5105cbc61330da0e55b22c00e2c1c4f.1722062145.git.christophe.jaillet@wanadoo.fr
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>