ykpers: fix compilation with GCC10

Signed-off-by: Rosen Penev <rosenp@gmail.com>

utils/ykpers/Makefile

@@ -2,7 +2,7 @@ include $(TOPDIR)/rules.mk
 
 PKG_NAME:=ykpers
 PKG_VERSION:=1.20.0
-PKG_RELEASE:=1
+PKG_RELEASE:=2
 
 PKG_SOURCE:=$(PKG_NAME)-$(PKG_VERSION).tar.gz
 PKG_SOURCE_URL:=https://developers.yubico.com/yubikey-personalization/Releases

utils/ykpers/patches/010-gcc10.patch

@@ -0,0 +1,13 @@
+--- a/ykpers-args.h
++++ b/ykpers-args.h
+@@ -33,8 +33,8 @@
+ 
+ #include "ykpers.h"
+ 
+-const char *usage;
+-const char *optstring;
++extern const char *usage;
++extern const char *optstring;
+ 
+ int args_to_config(int argc, char **argv, YKP_CONFIG *cfg, char *oathid,
+ 		   size_t oathid_len, const char **infname,