[POWERPC] fsl_soc: Fix trivial printk typo.

Fix a trivial printk typo in fsl_soc.

Cc: G. Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>