drm/amd/display: Remove unnecessary conversion to bool

Fix the following coccicheck warnings:

./drivers/gpu/drm/amd/display/dc/dcn30/dcn30_dpp_cm.c:298:33-38:
WARNING: conversion to bool not needed here.
Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Signed-off-by: Jiapeng Chong <jiapeng.chong@linux.alibaba.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/display/dc/dcn30/dcn30_dpp_cm.c

@@ -295,7 +295,7 @@ bool dpp3_program_gamcor_lut(
 	cm_helper_program_gamcor_xfer_func(dpp_base->ctx, params, &gam_regs);
 
 	dpp3_program_gammcor_lut(dpp_base, params->rgb_resulted, params->hw_points_num,
-			next_mode == LUT_RAM_A ? true:false);
+				 next_mode == LUT_RAM_A);
 
 	//select Gamma LUT to use for next frame
 	REG_UPDATE(CM_GAMCOR_CONTROL, CM_GAMCOR_SELECT, next_mode == LUT_RAM_A ? 0:1);