loader: More generic pre_exec for Linux (try 2)

[André Hentschel]

Am 29.12.2014 um 23:03 schrieb André Hentschel:
> ---
>  loader/main.c | 26 ++++++++++++++++++--------
>  1 file changed, 18 insertions(+), 8 deletions(-)

[After a small IRC discussion]

My main goal is to also get the 2G/2G vmsplit warning on ARM, too. (and potential other platforms)
There are still many ARM kernels out there with a 2G split.
The problem is that Wine can't start on 2G/2G, it seems there are too much assumptions in the code for a 3G split.
e.g. for shared user data. We can't allocate 0x7ffe0000-0x7fff0000 on 2G split, most likely something else is already there, idk