west: runners: Remove unnecessary constructors

These just pass their arguments through to the base class constructor.
Removing them means the base class constructor gets called directly
instead.

Fixes this pylint warning:

    W0235: Useless super delegation in method '__init__'
    (useless-super-delegation)

Fixing pylint warnings for a CI check.

Signed-off-by: Ulf Magnusson <Ulf.Magnusson@nordicsemi.no>