newlib: fix extract process for custom version

newlib: fix extract process for custom version

If the user specifies the use of a custom newlib version, the logic in the
extract function was reversed, so this step would fail.

Signed-off-by: Trevor Woerner <trevor.woerner@linaro.org>
[yann.morin.1998@free.fr: keep leading indentation]
Signed-off-by: "Yann E. MORIN" <yann.morin.1998@free.fr>
Message-Id: <c727adf1b7bd2c1e891d.1393353347@openSUSE-i7>
Patchwork-Id: 324060

     1.1 --- a/scripts/build/libc/newlib.sh	Mon May 05 23:24:33 2014 +0200
     1.2 +++ b/scripts/build/libc/newlib.sh	Tue Feb 25 13:34:48 2014 -0500
     1.3 @@ -29,7 +29,7 @@
     1.4  
     1.5  do_libc_extract() {
     1.6      # If using custom directory location, nothing to do
     1.7 -    if [    "${CT_LIBC_NEWLIB_CUSTOM}" != "y"            \
     1.8 +    if [    "${CT_LIBC_NEWLIB_CUSTOM}" = "y"             \
     1.9           -a -d "${CT_SRC_DIR}/newlib-${CT_LIBC_VERSION}" ]; then
    1.10          return 0
    1.11      fi