msm: net: ecm: add driver correct operational mode validation

In order to ensure that the driver APIs are called in the
correct order and each state transition keeps the driver
in a steady state a new mechanism is added.
This mechanism will keep a record of the driver state
and check between state
transition that the intended operation is allowed.
For example, make sure that the driver stop() method
won't be called before the open()/init() function was
called and etc.

Change-Id: Ia9ca67a734e89b008105165479b74c712db09a36
Signed-off-by: Talel Atias <tatias@codeaurora.org>