package/gnuradio: revert patch 003 removal

package/gnuradio: revert patch 003 removal

In commit 14476b7fcaf102dcc39b5d4919a4f08660f821de ("package/gnuradio:
bump to 3.8.1.0"), all gnuradio patches were dropped. However, it
turns out that the path
0003-gr-digital-glfsr.h-drop-boost-cstdint.hpp-and-use-cs.patch was
applied in gnuradio master branch but has not been backported to
maint-3.8.  So this patch can't be supressed as we are using gnuradio
3.8.1.0.

Fix:
  http://autobuild.buildroot.net/results/79a7dabc20016bcf11afe22e6a5691edbba2455b/
  http://autobuild.buildroot.net/results/7342833ebcc8f399d98ba05e63fce6b60403371e/
  http://autobuild.buildroot.net/results/1807c1b054623148f0a2e55dd998b0b428f48b47/

Signed-off-by: Gwenhael Goavec-Merou <gwenhael.goavec-merou@trabucayre.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>