cris: v10: axisflashmap: remove unused ifdefs

The Kconfig CONFIG_ETRAX_AXISFLASHMAP_MTD0WHOLE
does not exist for crisv10, so remove it.

Signed-off-by: Niklas Cassel <niklas.cassel@axis.com>
Signed-off-by: Jesper Nilsson <jespern@axis.com>