travis: remove -Werror

Using -Werror in CFLAGS make ./configure to fails with:
 checking whether the C compiler works... no
 configure: error: in `/home/travis/build/LudovicRousseau/libusb':
 configure: error: C compiler cannot create executables
 See `config.log' for more details

-Werror had no effect because CFLAGS was _not_ exported.

diff --git a/travis-autogen.sh b/travis-autogen.sh
index 2079933..dd3af0b 100755 (executable)
--- a/travis-autogen.sh
+++ b/travis-autogen.sh
@@ -35,7 +35,6 @@ CFLAGS+=" -Wno-deprecated-declarations"
 # should be removed and the code fixed
 CFLAGS+=" -Wno-incompatible-pointer-types-discards-qualifiers"
 
-# fails on warning
-CFLAGS+=" -Werror"
+export CFLAGS
 
 ./autogen.sh