toolchain: uClibc: fix build with CONFIG_BUILD_NLS selected

Without this patch, selecting "Compile with full language support"
results in the following question during build:

...
Locale Support (UCLIBC_HAS_LOCALE) [Y/n/?] y
  Locale data
  > 1. All locales (UCLIBC_BUILD_ALL_LOCALE) (NEW)
    2. Only selected locales (UCLIBC_BUILD_MINIMAL_LOCALE) (NEW)
    3. Use Pre-generated Locale Data (UCLIBC_PREGENERATED_LOCALE_DATA) (NEW)
  choice[1-3]:

Signed-off-by: Michael Heimpold <mhei@heimpold.de>

git-svn-id: svn://svn.openwrt.org/openwrt/trunk@43445 3c298f89-4303-0410-b956-a3cf2f4a3e73
toolchain: uClibc: fix compile with full language support enabled (fixes #13095)

When building with CONFIG_BUILD_NLS=y, uClibc fails to compile with following
message (or similar, according to https://dev.openwrt.org/ticket/13095):

-snip-
...
Warning: adding UNDEFINED entry for ar_AE
Warning: adding UNDEFINED entry for am_ET
Warning: adding UNDEFINED entry for af_ZA
grep "^#define" extra/locale/locale_tables.h > extra/locale/lt_defines.h
grep "^#define __lc" extra/locale/locale_collate.h >> extra/locale/lt_defines.h
gcc extra/locale/gen_wctype.c  -o extra/locale/gen_wctype    -Os -Wall  -D__UCLIBC_GEN_LOCALE -I./
extra/locale/gen_wctype.c: In function 'main':
extra/locale/gen_wctype.c:684:2: warning: #warning fix the upper bound on the upper/lower tables... save 200 bytes or so [-Wcpp]
for locale in  en_US en_GB; do \
                extra/locale/gen_wctype  $locale > extra/locale/wctables.h || \
                extra/locale/gen_wctype  $locale.UTF-8 > extra/locale/wctables.h || \
                extra/locale/gen_wctype  $locale.iso8859-1 > extra/locale/wctables.h && break; \
        done
make[4]: *** [extra/locale/wctables.h] Error 1
-snap-

This seems to also depend on the host system used, e.g. running a fresh
checkout on a Debian 7.6 system triggered this error, while running the
very same stuff on an Ubuntu 12.10 Quantal Quetzal does not trigger it.

This is the configuration I used:

-snip-
buildbot@buildbot:~/openwrt-nls.git$ scripts/diffconfig.sh
CONFIG_TARGET_ar71xx=y
CONFIG_TARGET_ar71xx_generic=y
CONFIG_TARGET_ar71xx_generic_Default=y
CONFIG_DEVEL=y
CONFIG_BUILD_NLS=y
CONFIG_DOWNLOAD_FOLDER="/srv/downloads/downloads"
-snap-

In the ticket mentioned above, a patch is referenced which solves this issue.

Note, that this issue is also present on 14.07.

Signed-off-by: Michael Heimpold <mhei@heimpold.de>

git-svn-id: svn://svn.openwrt.org/openwrt/trunk@43446 3c298f89-4303-0410-b956-a3cf2f4a3e73