drm/amd/display: Make variables declaration inside ifdef guard

Make variables declaration inside ifdef guard, as they are only used
inside the same ifdef guard. This remove some of the
-Wunused-but-set-variable warning.
Signed-off-by: Arthur Grillo <arthurgrillo@riseup.net>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/display/dc/dml/dcn31/display_mode_vba_31.c

@@ -878,7 +878,9 @@ static bool CalculatePrefetchSchedule(
 	double DSTTotalPixelsAfterScaler;
 	double LineTime;
 	double dst_y_prefetch_equ;
+#ifdef __DML_VBA_DEBUG__
 	double Tsw_oto;
+#endif
 	double prefetch_bw_oto;
 	double prefetch_bw_pr;
 	double Tvm_oto;
@@ -1060,7 +1062,9 @@ static bool CalculatePrefetchSchedule(
 
 	min_Lsw = dml_max(1, dml_max(PrefetchSourceLinesY, PrefetchSourceLinesC) / max_vratio_pre);
 	Lsw_oto = dml_ceil(4 * dml_max(prefetch_sw_bytes / prefetch_bw_oto / LineTime, min_Lsw), 1) / 4;
+#ifdef __DML_VBA_DEBUG__
 	Tsw_oto = Lsw_oto * LineTime;
+#endif
 
 
 #ifdef __DML_VBA_DEBUG__

drivers/gpu/drm/amd/display/dc/dml/dcn314/display_mode_vba_314.c

@@ -900,7 +900,9 @@ static bool CalculatePrefetchSchedule(
 	double DSTTotalPixelsAfterScaler;
 	double LineTime;
 	double dst_y_prefetch_equ;
+#ifdef __DML_VBA_DEBUG__
 	double Tsw_oto;
+#endif
 	double prefetch_bw_oto;
 	double prefetch_bw_pr;
 	double Tvm_oto;
@@ -1082,7 +1084,9 @@ static bool CalculatePrefetchSchedule(
 
 	min_Lsw = dml_max(1, dml_max(PrefetchSourceLinesY, PrefetchSourceLinesC) / max_vratio_pre);
 	Lsw_oto = dml_ceil(4 * dml_max(prefetch_sw_bytes / prefetch_bw_oto / LineTime, min_Lsw), 1) / 4;
+#ifdef __DML_VBA_DEBUG__
 	Tsw_oto = Lsw_oto * LineTime;
+#endif
 
 
 #ifdef __DML_VBA_DEBUG__