[SDL] [patch] fix sed expression in sdl-config

[Sam Lantinga]

> just noticed that sdl-config uses '[a-z]' with sed in sdl-config without 
> forcing the locale to C ... this could cause problems with locales where the 
> letter 'z' is not the last letter in the alphabet

Thanks!  Your patch is in subversion.

See ya,
	-Sam Lantinga, Senior Software Engineer, Blizzard Entertainment