libassuan: fix linking of host's libgpg-error

gpgrt-config is trying to use the host's /usr/lib path when looking for
libgpg-error. Therefore, disable it and gpg-error-config will be used
as a fallback.

Signed-off-by: Alexander Egorenkov <egorenar-dev@posteo.net>

libs/libassuan/Makefile

@@ -32,6 +32,9 @@ protocol. This protocol is used for IPC between most newer GnuPG
 components. Both, server and client side functions are provided. 
 endef
 
+CONFIGURE_VARS += \
+		ac_cv_path_GPGRT_CONFIG="no"
+
 define Build/InstallDev
 	$(INSTALL_DIR) $(2)/bin $(1)/usr/bin
 	$(INSTALL_BIN) \