spice: fix building against arc770-uclibc toolchain

Supersedes openwrt/packages#10873

Ref: https://github.com/openwrt/packages/pull/10873
Reported-by: Rosen Penev <rosenp@gmail.com>
Signed-off-by: Yousong Zhou <yszhou4tech@gmail.com>

libs/spice/patches/0003-disable-building-tests.patch

@@ -0,0 +1,14 @@
+Tests build can fail for arc700 for the following causes
+
+ - Missing -stack-protector-all argument when building test progs
+ - Missing linker flag -lgmodule-2.0 -lffi
+
+--- a/server/Makefile.am.orig	2019-12-25 18:31:59.133981942 +0800
++++ b/server/Makefile.am	2019-12-25 18:32:06.308976585 +0800
+@@ -1,5 +1,5 @@
+ NULL =
+-SUBDIRS = . tests
++SUBDIRS = .
+ 
+ check-valgrind:
+ 	$(MAKE) -C tests check-valgrind

libs/spice/patches/0004-fix-building-tools.patch

@@ -0,0 +1,12 @@
+Tools build can fail because -stack-protector-all is missing
+
+--- a/tools/Makefile.am.orig	2019-12-25 18:51:48.947959673 +0800
++++ b/tools/Makefile.am	2019-12-25 18:51:56.165952726 +0800
+@@ -8,6 +8,7 @@ AM_CPPFLAGS = \
+ 
+ AM_LDFLAGS = \
+ 	$(LIBRT) \
++	$(WARN_LDFLAGS) \
+ 	$(NULL)
+ 
+ noinst_PROGRAMS = \