msmtp: prevent use of IDN support on uClibc

Signed-off-by: Nicolas Thill <nico@openwrt.org>

mail/msmtp/Makefile

 
 PKG_NAME:=msmtp
 PKG_VERSION:=1.6.1
-PKG_RELEASE:=2
+PKG_RELEASE:=3
 
 PKG_SOURCE:=$(PKG_NAME)-$(PKG_VERSION).tar.xz
 PKG_SOURCE_URL:=@SF/msmtp
 	--without-libsecret \
 	--without-macosx-keyring \
 
+ifneq ($(CONFIG_USE_UCLIBC),)
+  CONFIGURE_ARGS += --disable-gai-idn
+endif
+
 MAKE_FLAGS :=
 
 ifeq ($(BUILD_VARIANT),ssl)