drm/amd/display: Fix uninitialized variables in dcn401

[WHAT & HOW]
surf_linear_128_l/c are used in CalculateBytePerPixelAndBlockSizes
before they are assigned, so initializing them before passing them into
the function.

This fixes 2 UNINIT issues reported by Coverity.
Reviewed-by: Rodrigo Siqueira <rodrigo.siqueira@amd.com>
Signed-off-by: Alex Hung <alex.hung@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/display/dc/dml2/dml21/src/dml2_core/dml2_core_dcn4_calcs.c

@@ -11521,8 +11521,8 @@ void dml2_core_calcs_get_dpte_row_height(
 	unsigned int MacroTileWidthC;
 	unsigned int MacroTileHeightY;
 	unsigned int MacroTileHeightC;
-	bool surf_linear_128_l;
-	bool surf_linear_128_c;
+	bool surf_linear_128_l = false;
+	bool surf_linear_128_c = false;
 
 	CalculateBytePerPixelAndBlockSizes(
 		SourcePixelFormat,