remove Retro-Ball [migrated to 4sports]

fixes https://github.com/a2-4am/4cade/issues/727

src/prelaunch/rb.a

@@ -1,69 +0,0 @@
-;license:MIT
-;(c) 2022, 2024 by qkumba/Frank M.
-
-!cpu 6502
-!to "build/PRELAUNCH.INDEXED/RB",plain
-*=$106
-
-         !source "src/macros.a"
-
-         +READ_RAM2_NO_WRITE
-         jsr   HideLaunchArtworkLC2
-
-         lda   WaitForVBL
-         cmp   #$60
-         beq   novbl1
-         jsr   EnableAccelerator
-         lda   #0
-         sta   $5FFC      ; enable our VBL
-
-novbl1
-         lda   #$4C
-         sta   $6127
-         lda   #<callback0
-         sta   $6128
-         lda   #>callback0
-         sta   $6129
-
-         lda   #$4C
-         sta   $612F
-         lda   #<callback1
-         sta   $6130
-         lda   #>callback1
-         sta   $6131
-
-         jmp   $3FF8      ; decompress & show title
-
-callback0
-         lda   #0
-         sta   $2000      ; remove activity indicator
--        lda   $C000      ; and wait for keypress
-         bpl   -
-         jmp   $8F3
-
-callback1
-         lda   WaitForVBL
-         cmp   #$60
-         beq   novbl2
-         lda   #$4C
-         sta   $14F9
-         lda   #<callback2
-         sta   $14FA
-         lda   #>callback2
-         sta   $14FB
-
-novbl2
-         lda   $C055
-         jsr   DisableAccelerator
-         +READ_ROM_NO_WRITE
-         rts
-
-callback2
-         +READ_RAM2_NO_WRITE
-         jsr   WaitForVBL
-         +READ_ROM_NO_WRITE
-         rts
-
-!if * > PrelaunchMax {
-  !error "code is too large, ends at ", *
-}