char/nvram: Re-order functions to remove forward declarations and #ifdefs

Also give functions more sensible names: nvram_misc_* for misc device ops,
nvram_proc_* for proc file ops and nvram_module_* for init and exit
functions. This prevents name collisions with nvram.h helper functions
and improves readability.

Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>