feat(intel): implement timer init divider via CPU frequency for N5X

Get CPU frequency and update the timer init div with it.
The timer is vary based on the CPU frequency instead of hardcoded.

Signed-off-by: Jit Loon Lim <jit.loon.lim@intel.com>
Signed-off-by: Sieu Mun Tang <sieu.mun.tang@intel.com>
Change-Id: Ibfaa47fb7a25176eebf06f4828bf9729d56f12ed
diff --git a/plat/intel/soc/stratix10/include/s10_clock_manager.h b/plat/intel/soc/stratix10/include/s10_clock_manager.h
index cf57df3..661e204 100644
--- a/plat/intel/soc/stratix10/include/s10_clock_manager.h
+++ b/plat/intel/soc/stratix10/include/s10_clock_manager.h
@@ -95,5 +95,6 @@
 uint32_t get_mmc_clk(void);
 uint32_t get_l3_clk(uint32_t ref_clk);
 uint32_t get_ref_clk(uint32_t pllglob);
+uint32_t get_cpu_clk(void);
 
 #endif