m68k: clean up unused "config ROMVECSIZE"

Kconfig symbol ROMVECSIZE is unused since commit
f84f52a5 ("m68knommu: clean up linker
script"). Let's clean up its Kconfig entry too.
Signed-off-by: Paul Bolle <pebolle@tiscali.nl>
Signed-off-by: Greg Ungerer <gerg@uclinux.org>

arch/m68k/Kconfig.machine

@@ -539,15 +539,6 @@ config ROMVEC
 	  68000 type variants the vectors are at the base of the boot device
 	  on system startup.
 
-config ROMVECSIZE
-	hex "Size of ROM vector region (in bytes)"
-	default "0x400"
-	depends on ROM
-	help
-	  Define the size of the vector region in ROM. For most 68000
-	  variants this would be 0x400 bytes in size. Set to 0 if you do
-	  not want a vector region at the start of the ROM.
-
 config ROMSTART
 	hex "Address of the base of system image in ROM"
 	default "0x400"