rtc/qmsi: Fix the IRQ priority setting according to the SoC specific option

The configuration option CONFIG_RTC_IRQ_PRI does not longer exist, and have
to use the specific QMSI driver IRQ priority

Change-Id: I8074c6d8e095596d03e51a94f26a73c3a9ff91b7
Signed-off-by: Sergio Rodriguez <sergio.sf.rodriguez@intel.com>