drm/i915/gt: fix typo issue

Change 'freqency' to 'frequency'.
Signed-off-by: wengjianfeng <wengjianfeng@yulong.com>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210520080646.24132-1-samirweng1979@163.com

drivers/gpu/drm/i915/gt/selftest_rps.c

@@ -606,7 +606,7 @@ int live_rps_frequency_cs(void *arg)
 	int err = 0;
 
 	/*
-	 * The premise is that the GPU does change freqency at our behest.
+	 * The premise is that the GPU does change frequency at our behest.
 	 * Let's check there is a correspondence between the requested
 	 * frequency, the actual frequency, and the observed clock rate.
 	 */
@@ -747,7 +747,7 @@ int live_rps_frequency_srm(void *arg)
 	int err = 0;
 
 	/*
-	 * The premise is that the GPU does change freqency at our behest.
+	 * The premise is that the GPU does change frequency at our behest.
 	 * Let's check there is a correspondence between the requested
 	 * frequency, the actual frequency, and the observed clock rate.
 	 */