git: update to v2.17.1

Update to git version v2.17.1. Required changes:

* The function 'typename' has been renamed to 'type_name'
  (upstream commit debca9d2fe784193dc2d9f98b5edac605ddfefbb)

Signed-off-by: Christian Hesse <mail@eworm.de>

Makefile

@@ -14,7 +14,7 @@ htmldir = $(docdir)
 pdfdir = $(docdir)
 mandir = $(prefix)/share/man
 SHA1_HEADER = <openssl/sha.h>
-GIT_VER = 2.16.0
+GIT_VER = 2.17.1
 GIT_URL = https://www.kernel.org/pub/software/scm/git/git-$(GIT_VER).tar.gz
 INSTALL = install
 COPYTREE = cp -r