debug/gdb: remove ncurses cleanup

That's legacy code that was usefull when ncurses was installed
in the sysroot. Still it's not longer the case (it's installed
in a special dedicated directory), we can remove that piece of
code.

Signed-off-by: "Yann E. MORIN" <yann.morin.1998@free.fr>

 CT_EXPERIMENTAL=y

 CT_LOCAL_TARBALLS_DIR="${HOME}/src"

 CT_SAVE_TARBALLS=y

 CT_LOG_EXTRA=y

 CT_ARCH_CPU="cpu32"

 CT_ARCH_m68k=y

 CT_ARCH_BINFMT_FLAT=y

 CT_BINUTILS_V_2_20_1a=y

 CT_CC_V_4_3_4=y

 CT_LIBC_none=y

 CT_GMP_V_4_3_2=y

 CT_MPFR_V_2_4_2=y