ARM: imx: Kconfig: Remove IMX_HAVE_PLATFORM_IMX_SSI from MACH_MX25_3DS

commit 5fb86e5d

 (ARM: mx31_3ds: Add sound support) added audio support for
mx31pdk, but touched MACH_MX25_3DS Kconfig by mistake.

Remove IMX_HAVE_PLATFORM_IMX_SSI from MACH_MX25_3DS configuration.

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>