the __strerror() and __strsignal() functions can not assume that the
messages will not overflow a NL_TEXTSIZE-sized buffer.
Noted by Mike Long <mike.long@analog.com> in PR
and use message catalogs if NLS is defined.
Increased the size of char buffers used by strerror() and strsignal();
the error and signal strings may be much longer in some locales.