Cleanup: use "_pad" prefix for pad vars

source/blender/makesdna/DNA_light_types.h

@@ -52,7 +52,8 @@ typedef struct Light {
 
 	/** Quad1 and Quad2 attenuation. */
 	float att1, att2;
-	float coeff_const, coeff_lin, coeff_quad, coeff_pad;
+	float coeff_const, coeff_lin, coeff_quad;
+	char _pad0[4];
 	struct CurveMapping *curfalloff;
 	short falloff_type;
 	char _pad2[2];

source/blender/makesdna/DNA_particle_types.h

@@ -217,7 +217,8 @@ typedef struct ParticleSettings {
 	float timetweak, courant_target;
 	float jitfac, eff_hair, grid_rand, ps_offset[1];
 	int totpart, userjit, grid_res, effector_amount;
-	short time_flag, time_pad[3];
+	short time_flag;
+	char _pad0[6];
 
 	/* initial velocity factors */
 	float normfac, obfac, randfac, partfac, tanfac, tanphase, reactfac;

source/blender/makesdna/DNA_scene_types.h

@@ -158,7 +158,7 @@ typedef struct FFMpegCodecData {
 	int audio_bitrate;
 	int audio_mixrate;
 	int audio_channels;
-	int audio_pad;
+	char _pad0[4];
 	float audio_volume;
 	int gop_size;
 	/** Only used if FFMPEG_USE_MAX_B_FRAMES flag is set. */