nano: Update to 8.4

nano: Update to 8.4

Update nano edit to version 8.4.

Add configure flags to overcome upstream bug 66978, where the newly added
gnulib module for strcasecmp always fails in the configure step when
cross-compiling.
https://savannah.gnu.org/bugs/?66978
https://github.com/coreutils/gnulib/commit/b2927d1b1fa3fb09a2210a3df5691f7d48d6151b

The added flags disable the strcasecmp function from gnulib.
If upstream (gnulib?) fixes things later, the flags should be removed.

Signed-off-by: Hannu Nyman <redacted>