soc/samsung/exynos5250/clk.h: Trivial, fix spelling in comments

Change-Id: Iaacd4d7977ddeff4204acdc32d4d13fd88b6660b
Signed-off-by: Edward O'Callaghan <eocallaghan@alterapraxis.com>
Reviewed-on: http://review.coreboot.org/7928
Tested-by: build bot (Jenkins)
Reviewed-by: Alexandru Gagniuc <mr.nuke.me@gmail.com>

src/soc/samsung/exynos5250/clk.h

@@ -58,11 +58,11 @@ unsigned long get_uart_clk(int dev_index);
 void set_mmc_clk(int dev_index, unsigned int div);
 
 /**
- * get the clk frequency of the required peripherial
+ * get the clk frequency of the required peripheral
  *
- * @param peripherial	Peripherial id
+ * @param peripheral	Peripheral id
  *
- * @return frequency of the peripherial clk
+ * @return frequency of the peripheral clk
  */
 unsigned long clock_get_periph_rate(enum periph_id peripheral);
 
@@ -83,7 +83,7 @@ int clock_set_mshci(enum periph_id peripheral);
 /*
  * Sets the epll clockrate
  *
- * @param rate	Required clock rate to the presacaler in Hz
+ * @param rate	Required clock rate to the prescaler in Hz
  *
  * Return	0 if ok else -1
  */