clk: davinci: Add NULL check in davinci_lpsc_clk_register()

clk: davinci: Add NULL check in davinci_lpsc_clk_register()

devm_kasprintf() returns NULL when memory allocation fails. Currently,
davinci_lpsc_clk_register() does not check for this case, which results
in a NULL pointer dereference.

Add NULL check after devm_kasprintf() to prevent this issue and ensuring
no resources are left allocated.

Fixes: c6ed4d734bc7 ("clk: davinci: New driver for davinci PSC clocks")
Signed-off-by: Henry Martin <bsdhenrymartin@gmail.com>
Link: https://lore.kernel.org/r/20250401131341.26800-1-bsdhenrymartin@gmail.com
Reviewed-by: David Lechner <david@lechnology.com>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>