platform: nordic_nrf: Replace deprecated enum for timer prescaler

This commit replaces deprecated nrf_timer_frequency_t enum with
new numerical value.

Change-Id: Id65381bef95469ff9da28b066108bdcf99c8773d
Signed-off-by: Adam Wojasinski <adam.wojasinski@nordicsemi.no>
Signed-off-by: Joakim Andersson <joakim.andersson@nordicsemi.no>
2 files changed