Straignten out some issues with HAVE_LCD_ENABLE. 1g/2g/3g had it defined but it shouldn't have been. lcd_enabled() was only available as a real function on gigabeat but others can use that too. Markup lcd.h a bit because I got a bit lost in it.

git-svn-id: svn://svn.rockbox.org/rockbox/trunk@14100 a1c6a512-1295-4272-9138-f99709370657
8 files changed