[nrf fromtree] drivers: dp: swdp_bitbang: hardcode nRF53 SYSCLK

Since CONFIG_SYS_CLOCK_HW_CYCLES_PER_SEC is tied to the slow RTC clock
for the nRF53, use the default SYSCLK of 64MHz instead.

Signed-off-by: Maximilian Deubel <[email protected]>
(cherry picked from commit 621a600)

Author: maxd-nordic

drivers/dp/swdp_ll_pin.h

@@ -6,8 +6,9 @@
 
 #include <zephyr/kernel.h>
 #include <zephyr/drivers/gpio.h>
+#include <soc.h>
 
-#if defined(CONFIG_SOC_SERIES_NRF52X)
+#if defined(CONFIG_SOC_SERIES_NRF52X) || defined(CONFIG_SOC_SERIES_NRF53X)
 #define CPU_CLOCK		64000000U
 #else
 #define CPU_CLOCK		CONFIG_SYS_CLOCK_HW_CYCLES_PER_SEC