Use constants for menu flags

Added a bunch of constants for the bitflags of each kind of menu. Some
are slightly vague or too long, but I'm not sure how to else name them.

engine/delete_save_change_clock.asm

@@ -47,14 +47,14 @@ _ResetClock: ; 4d3b1
 	db "@"
 
 .NoYes_MenuDataHeader: ; 0x4d40d
-	db $00 ; flags
+	db 0 ; flags
 	db 07, 14 ; start coords
 	db 11, 19 ; end coords
 	dw .NoYes_MenuData2
 	db 1 ; default option
 
 .NoYes_MenuData2: ; 0x4d415
-	db $c0 ; flags
+	db STATICMENU_CURSOR | STATICMENU_NO_TOP_SPACING ; flags
 	db 2 ; items
 	db "NO@"
 	db "YES@"
@@ -285,14 +285,14 @@ _DeleteSaveData: ; 4d54c
 	db "@"
 
 .NoYesMenuDataHeader: ; 0x4d585
-	db $00 ; flags
+	db 0 ; flags
 	db 07, 14 ; start coords
 	db 11, 19 ; end coords
 	dw .MenuData2
 	db 1 ; default option
 
 .MenuData2: ; 0x4d58d
-	db $c0 ; flags
+	db STATICMENU_CURSOR | STATICMENU_NO_TOP_SPACING ; flags
 	db 2 ; items
 	db "NO@"
 	db "YES@"