[POWERPC] spufs: various run.c cleanups

 - remove the spu_acquire_runnable from spu_run_init.  I need to
   opencode it in spufs_run_spu in the next patch
 - remove various inline attributes, we don't really want to inline
   long functions with multiple callsites
 - cleanup return values and runcntl_write calls in spu_run_init
 - use normal kernel codingstyle in spu_reacquire_runnable

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>