package/collectd: add DPDK_TELEMETRY option

DPDK support is available since version 5.11.0 and
https://github.com/collectd/collectd/commit/00cbd4d2c016a676db476ae66bbc58d6bf11a6a0

It depends on jansson and is currently enabled by default raising the
following build failure on musl:

src/dpdk_telemetry.c:43:10: fatal error: sys/unistd.h: No such file or directory
 #include <sys/unistd.h>
          ^~~~~~~~~~~~~~

Fixes:
 - http://autobuild.buildroot.org/results/aafb8c72f147fefc7a988c45e4dc17de48b07a95



Signed-off-by: Fabrice Fontaine <fontaine.fabrice@gmail.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>