Verify that there aren't too many OAM constants

Fixes #1062

constants/battle_anim_constants.asm

@@ -713,6 +713,9 @@ DEF NUM_BATTLEANIMFRAMESETS EQU const_value
 	const BATTLEANIMOAMSET_D7
 DEF NUM_BATTLEANIMOAMSETS EQU const_value
 
+assert NUM_BATTLEANIMOAMSETS <= FIRST_OAM_CMD, \
+	"BATTLEANIMOAMSET_* constants overlap oam*_command constants"
+
 ; BattleBGEffects indexes (see engine/battle_anims/bg_effects.asm)
 	const_def 1
 	const ANIM_BG_FLASH_INVERTED

constants/sprite_anim_constants.asm

@@ -334,3 +334,6 @@ DEF NUM_SPRITE_ANIM_FRAMESETS EQU const_value
 	const SPRITE_ANIM_OAMSET_GAMEFREAK_LOGO_10           ; 8a
 	const SPRITE_ANIM_OAMSET_GAMEFREAK_LOGO_11           ; 8b
 DEF NUM_SPRITE_ANIM_OAMSETS EQU const_value
+
+assert NUM_SPRITE_ANIM_OAMSETS <= FIRST_OAM_CMD, \
+	"SPRITE_ANIM_OAMSET_* constants overlap oam*_command constants"