USB: ehci-s5p : use __devinit and __devexit macros for probe and remove

The __devinit and __devexit macros were added to probe and remove
functions. The macros move the probe and remove functions to the
devinit and devexit sections

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>