[Patch] Don't provide lstat gfortran intrinsic if target doesn't support lstat.

[FX Coudert]

>> It could be applied, since it's a regression wrt g77. As GCC >= 4.0.0
>> is not used by the mingw project, I thought it was not high-priority
>> to backport it. But, as I recently read Danny saying he'll make a
>> MinGW GCC-4.2.0 candidate when 4.2.0 is released, it is probably a
>> good reason to do it.
>
> Seconded.

Commited to 4.2.

FX