gpu: fix typos in code comments

fix eror to error
Signed-off-by: Weitao Hou <houweitaoo@gmail.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/display/dc/dce/dce_clock_source.c

@@ -183,8 +183,8 @@ static bool calculate_fb_and_fractional_fb_divider(
 *RETURNS:
 * It fills the PLLSettings structure with PLL Dividers values
 * if calculated values are within required tolerance
-* It returns	- true if eror is within tolerance
-*		- false if eror is not within tolerance
+* It returns	- true if error is within tolerance
+*		- false if error is not within tolerance
 */
 static bool calc_fb_divider_checking_tolerance(
 		struct calc_pll_clock_source *calc_pll_cs,