tools/expat: fix PKG_CPE_ID

cpe:/a:libexpat_project:libexpat is the correct CPE ID for expat:
https://nvd.nist.gov/products/cpe/search/results?keyword=cpe:2.3:a:libexpat_project:libexpat

Fixes: ff59f3f (tools/expat: fix PKG_CPE_ID)
Signed-off-by: Fabrice Fontaine <fontaine.fabrice@gmail.com>
Link: openwrt/openwrt#22406
Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>
(cherry picked from commit 3c3e56a)

Author: ffontaine

tools/expat/Makefile

@@ -8,7 +8,7 @@
 include $(TOPDIR)/rules.mk
 
 PKG_NAME:=expat
-PKG_CPE_ID:=cpe:/a:libexpat:libexpat
+PKG_CPE_ID:=cpe:/a:libexpat_project:libexpat
 PKG_VERSION:=2.7.3
 
 PKG_SOURCE:=$(PKG_NAME)-$(PKG_VERSION).tar.gz