lib: restore developer mode checks
lib: restore developer mode checks

Most of the checks on developer_mode have been accidentally dropped.
Restore them.

Fixes: 7d611e35b077 ("lib: simplify main build file")

Signed-off-by: David Marchand <f28529695cfa9e3e1eb84e7072aa626af4abb18e@redhat.com>
Acked-by: Bruce Richardson <66b9e8e8fbd5e9f41f91b0af050876182ce9d0e4@intel.com>

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