eal: fix memory leak on control thread failure
eal: fix memory leak on control thread failure

params is not freed if pthread_create() fails. The fix is
straight-forward.

Fixes: 3d09a6e26d8b ("eal: fix threads block on barrier")

Reported-by: Olivier Matz <dfcc1510895413197abb4336e39bb0a3906cba71@6wind.com>
Signed-off-by: Jianfeng Tan <4339d9ba3a87a0d192e405945005ff86667f7b0c@intel.com>
Reviewed-by: Olivier Matz <dfcc1510895413197abb4336e39bb0a3906cba71@6wind.com>

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