keepalived: add patch to disable PIE

keepalived: add patch to disable PIE

PIE breaks the build on m68k and Microblaze, so let's add a patch that
disables using PIE by default in keepalived. Obviously, when we start
seriously testing the BR2_RELRO_FULL option, we will realize that it
is broken on some architectures, and will probably disable it on m68k
and Microblaze.

Fixes:

  http://autobuild.buildroot.net/results/a536f5947b3b70fdaecad1af5542572c504ad046/
  http://autobuild.buildroot.net/results/0ffbf1e8d181c9463847a5b2be6f9baa18face24/

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>