procps-ng: fix BR2_STATIC_LIBS=y build

procps-ng: fix BR2_STATIC_LIBS=y build

The procps-ng package currently fails to build on BR2_STATIC_LIBS=y
configurations. Indeed, by default NUMA support is enabled, and it
requires dlopen(). As hinted by the configure script, passing
--disable-numa allows to disable NUMA support.

However, once this is done, another issue pops up: dlopen() is also used
by the SELinux support. But even when SELinux support is disabled, the
procps-ng code incorrectly includes <dlfcn.h>. This is addressed by the
addition of a patch.

Fixes:

  http://autobuild.buildroot.net/results/b385bf435085728aece6323a5006ba9fa6631744/

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>