kconfig: fix ncurses headers location

On some distors (eg. latesst openSuSE), the ncurses headers are not
located in the usual location.

Hard-code this location in the kconfig Makefile, as a (temporary?)
workaround.

Reported-by: Simon Gornall <sgornall@apple.com>
[Fix suggested by Simon]
Signed-off-by: "Yann E. MORIN" <yann.morin.1998@free.fr>

# Blackfin specific configuration file

## select ARCH_SUPPORTS_32

## select ARCH_DEFAULT_32

## select ARCH_DEFAULT_LE

## select ARCH_SUPPORTS_WITH_ARCH

## select ARCH_SUPPORTS_WITH_CPU

## select ARCH_SUPPORTS_WITH_TUNE

## select ARCH_SUPPORTS_WITH_FPU

##

## help The Blackfin architecture