Makefile: Fix CDPATH problem
If CDPATH is set, "cd" prints its destination to stdout, causing
the common (cd a && tar cf - .) | (cd b && tar xf -) idiom to fail.
For example:
make -C templates DESTDIR='' install
make[1]: Entering directory `/users/
e477610/exptool/src/git-1.7.0.2/templates'
install -d -m 755 '/home/
e477610/exptool/share/git-core/templates'
(cd blt && gtar cf - .) | \
(cd '/home/
e477610/exptool/share/git-core/templates' && umask 022 && gtar xof -)
gtar: This does not look like a tar archive
Most git scripts already protect against use of CDPATH through
git-sh-setup, but the Makefile doesn’t.
Reported-by: Michael Cox <mhcox@bluezoosoftware.com>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>