app/testpmd: limit port mask bits to configured maximum
app/testpmd: limit port mask bits to configured maximum

The port mask parsing in testpmd allowed up to 64 bits to be processed,
even if RTE_MAX_ETHPORTS is set to a max of 32. Fix this by only
processing up to min(RTE_MAX_ETHPORTS,64) bits of the mask.

Signed-off-by: Bruce Richardson <66b9e8e8fbd5e9f41f91b0af050876182ce9d0e4@intel.com>
Acked-by: Neil Horman <3316dc2d77df57653443c0391a5296176d6ca9c3@tuxdriver.com>

msune/dpdk,john-mcnamara-intel/dpdk,tsphillips/dpdk-fork,tsphillips/dpdk-fork,venkynv/dpdk-mirror,john-mcnamara-intel/dpdk,john-mcnamara-intel/dpdk,tsphillips/dpdk-fork,john-mcnamara-intel/dpdk,msune/dpdk,msune/dpdk,mixja/dpdk,tsphillips/dpdk-fork,mixja/dpdk,mixja/dpdk,venkynv/dpdk-mirror,venkynv/dpdk-mirror,msune/dpdk,mixja/dpdk,venkynv/dpdk-mirror