package/expat: bump to version 2.7.1
Changelog:
https://github.com/libexpat/libexpat/blob/R_2_7_1/expat/Changes
Update hash of the COPYING file (year updated):
https://github.com/libexpat/libexpat/commit/2b2a24691a9888e0f3c179b8f05cbacb19f460ef
Signed-off-by: Kadambini Nema <kadambini.nema@gmail.com>
Signed-off-by: Julien Olivain <ju.o@free.fr>
(cherry picked from commit de3e07d6fd9a452c58071024cbc539b5c6f7a526)
Signed-off-by: Thomas Perale <thomas.perale@mind.be>