debian/patches/git-updates.diff: update from upstream stable branch:

* debian/patches/git-updates.diff: update from upstream stable branch:
  - Fix stack buffer overflow in realpath() (CVE-2018-11236).  Closes:
    #899071.
  - Fix buffer overflow in AVX-512-optimized implementation of mempcpy()
    (CVE-2018-11237).  Closes: #899070.
  - Fix crashes with binaries using vtable interposition.  Closes:
    #861116.
  - debian/patches/arm/unsubmitted-ldso-abi-check.diff: refresh, sigh.