mark some functions as init functions (discarded after init() has run)
tick_start, fmradio_i2c_init, pcm_init, pcm_postinit, pcm_play_dma_init
Also add some as3525 target specific functions
Make as3525v2 use this attribute
git-svn-id: svn://svn.rockbox.org/rockbox/trunk@26328 a1c6a512-1295-4272-9138-f99709370657