valgrind: bump version to 3.11.0

- rebase patch 0001-workaround-SIGSEGV-on-PPC.patch
- remove upstream applied patches
  0002-Fix-configure-for-Linux-kernel-4.0-rc1.patch
  0004-configure.ac-Generalize-glibc-version-check.patch
- rebase 0003-add-missing-ptrace-getsiginfo-on-powerpc.patch
  (convert to git patch format, rename to
  0002-Define-PTRACE_GETSIGINFO-on-PowerPC-when-not-availab.patch)
- remove legacy VALGRIND_AUTORECONF=YES (no more patch touching confgure.ac)
- add '--disable-ubsan' for new undefined behaviour sanitiser option

Signed-off-by: Peter Seiderer <ps.report@gmx.net>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>