telemetry: fix error checking for strchr function
telemetry: fix error checking for strchr function

The strchr function return was not being checked which could lead to
NULL deferencing later in the function.

Coverity issue: 358438, 358445
Fixes: b80fe1805eee ("telemetry: introduce backward compatibility")

Signed-off-by: Ciara Power <2dd8f648091a527a3f34edd30b226be01da76a0e@intel.com>
Acked-by: Kevin Laatz <961b59698dfa2327ef66e48c81ae3315f5733fd1@intel.com>

john-mcnamara-intel/dpdk,john-mcnamara-intel/dpdk,john-mcnamara-intel/dpdk,john-mcnamara-intel/dpdk