download_externals: Fix GMP download URL.
Change-Id: Iad5f96a6f85e613214cbe75aba8594b673a1aa64
diff --git a/aos/build/download_externals.sh b/aos/build/download_externals.sh
index 50eec85..11070f9 100755
--- a/aos/build/download_externals.sh
+++ b/aos/build/download_externals.sh
@@ -150,7 +150,7 @@
GMP_DIR=${COMPILED}/gmp-${GMP_VERSION}
GMP_PREFIX=${GMP_DIR}-prefix
GMP_LIB=${GMP_PREFIX}/lib/libgmp.a
-GMP_URL=ftp://ftp.gmplib.org/pub/gmp/gmp-${GMP_VERSION}.tar.lz
+GMP_URL=https://gmplib.org/download/gmp/gmp-${GMP_VERSION}.tar.lz
[ -f ${GMP_TAR} ] || wget ${GMP_URL} -O ${GMP_TAR}
[ -d ${GMP_DIR} ] || ( mkdir ${GMP_DIR} && tar \
--strip-components=1 -C ${GMP_DIR} -xf ${GMP_TAR} )