Revert "staging: imx: fix non-static declarations"

This reverts commit 9a5a6911 as it
causes unneeded build warnings :(

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: JB Van Puyvelde <jbvanpuyvelde@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>