lisa._assets.kmodules.lisa: Add config macro system

FEATURE

Add crude config macro system that will default to enable all config
options, unless they were explicitly disabled.

Each config option is prefixed with LISA_CONFIG_ and takes a 0 or 1
value. This is _not_ like Kconfig, where enabling disabling is based on
being defined or not. LISA_CONFIG_ can be defined to 0, meaning the
option is disabled.