parameters: Add lazy cache

Add a lazy cache that fetches the parameters on demand
when they are used the first time.

Change the api to instantiate the ParameterAccess() as
sysparam when you import the module, that's now possible
with the lazy cache.

Add a __call__() method for backwards compatibility while
we do the migration

Change-Id: Ie1d447a85c2b66130b368c93265c4be6cf8c2286
parameters: Use sysparam instead of sysparam()

Update all the callsites which avoids the extra ()

Change-Id: I83f6ec5ff6509c0aa23721b19e3373382939a461
parameters: Avoid instantiating sysparam

Migrate the remaining callsites to use sysparam directly

Change-Id: Idfca373394117aa3e3170dd94a2246878ce8f73a
parameters: Remove __call__

It's no longer used, all callsites have been migrated.

Change-Id: Ica81a9c9ad7c1c0ddbc0250fa4bb824763833738