The ARM SHA-1 implementation was removed by commit 30ae47b
(remove ARM and Mozilla SHA1 implementations, 2009-08-17). Prune
its directory from the list of object files to delete in 'make
clean'.
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>