e1000e: cleanup boolean logic

Replace occurrences of 'if (<bool expr> == <1|0>)' with
'if ([!]<bool expr>)'

Replace occurrences of '<bool var> = (<non-bool expr>) ? true : false'
with '<bool var> = <non-bool expr>'.

Replace occurrence of '<bool var> = <non-bool expr>' with
'<bool var> = !!<non-bool expr>'

While the latter replacement is not really necessary, it is done here for
consistency and clarity.  No functional changes.

Signed-off-by: Bruce Allan <bruce.w.allan@intel.com>
Tested-by: Aaron Brown <aaron.f.brown@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>