Fix BSP/imxrt/imxrt1060-nxp-evk: RTC Driver issue (#6283)
Fix BSP/imxrt/imxrt1060-nxp-evk: RTC Driver issue (#6283)

Fix BSP bug:
-Function naming conflict in drv_rtc.c, rename get/set_timestamp to imxrt_hp_get/set_timestamp, which conflicted with rtc.c/.h framework.
RT-Thread/rt-thread,RT-Thread/rt-thread,RT-Thread/rt-thread,RT-Thread/rt-thread,RT-Thread/rt-thread,RT-Thread/rt-thread,RT-Thread/rt-thread