clk: at91: peripheral: convert from round_rate() to determine_rate()

clk: at91: peripheral: convert from round_rate() to determine_rate()

The round_rate() clk ops is deprecated, so migrate this driver from
round_rate() to determine_rate() using the Coccinelle semantic patch
on the cover letter of this series.

This driver already has a clk_sam9x5_peripheral_determine_rate()
implementation, however it can change the parent rate. The existing
round rate does not have this functionality. I could add a check
for CLK_SET_RATE_PARENT, and combine the two functions, however there
are some other minor differences in the two implementations. I don't
have access to this particular hardware. I believe that they could
be combined, however it would need to be tested on real hardware.
So, let's play it safe and convert the existing round rate
implementation to ensure that the driver keeps the same functionality
as before.

Reviewed-by: Alexander Sverdlin <alexander.sverdlin@gmail.com>
Signed-off-by: Brian Masney <bmasney@redhat.com>