scripts: add verbose option in build test help
scripts: add verbose option in build test help

The verbose option was available but not advertised.

Fixes: 6e38dfe21389 ("scripts: add verbose test build option")

Signed-off-by: Thomas Monjalon <ee2fa8b2681c737f775687e475dcbf2028a412f1@6wind.com>

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