[SDL] Bug in 1.1.7 / MacOS

[Sam Lantinga]

> 1.1.7 introduced a new bug for the MacOS port. In file 
> SDL_macevents.c, lines 103ff, it reads:

> #if TARGET_API_MAC_CARBON
> #define cooperative_multitasking 1
> #else
> #define cooperative_multitasking 0
> #endif

This flag just means do we cooperate with MacOS task switching or not.
With the given values, MacOS classic apps will hog the display so that
you cannot switch to another application, while carbon apps will be a
little more Finder-friendly.

See ya!
	-Sam Lantinga, Lead Programmer, Loki Entertainment Software