[openwrt/openwrt] expat: Update to 2.7.3

[LEDE Commits]

thess pushed a commit to openwrt/openwrt.git, branch main:
https://git.openwrt.org/842623a4f82411821f8632f7f04511332bb6d47a

commit 842623a4f82411821f8632f7f04511332bb6d47a
Author: Ted Hess <thess at kitschensync.net>
AuthorDate: Sat Sep 27 17:46:18 2025 -0400

    expat: Update to 2.7.3
    
    Fixes:
        CVE-2025-59375
        Regression from: CVE-2024-8176
    
    Changelog: https://github.com/libexpat/libexpat/blob/R_2_7_3/expat/Changes
    
    Signed-off-by: Ted Hess <thess at kitschensync.net>
---
 tools/expat/Makefile | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/tools/expat/Makefile b/tools/expat/Makefile
index 8e46aa989e..afbc6f4f77 100644
--- a/tools/expat/Makefile
+++ b/tools/expat/Makefile
@@ -9,10 +9,10 @@ include $(TOPDIR)/rules.mk
 
 PKG_NAME:=expat
 PKG_CPE_ID:=cpe:/a:libexpat:libexpat
-PKG_VERSION:=2.7.1
+PKG_VERSION:=2.7.3
 
 PKG_SOURCE:=$(PKG_NAME)-$(PKG_VERSION).tar.gz
-PKG_HASH:=0cce2e6e69b327fc607b8ff264f4b66bdf71ead55a87ffd5f3143f535f15cfa2
+PKG_HASH:=821ac9710d2c073eaf13e1b1895a9c9aa66c1157a99635c639fbff65cdbdd732
 PKG_SOURCE_URL:=https://github.com/libexpat/libexpat/releases/download/R_$(subst .,_,$(PKG_VERSION))
 
 HOST_BUILD_PARALLEL:=1