usb: fsl_mxc_udc.c: Remove compile-time dependency of MX35 SoC type

In order to support multiple SoC kernel image, compile-time dependency
on a specific SoC type should be avoided.

fsl_udc_clk_finalize is already protected by cpu_is_mx35(), so remove
the compile-time check for CONFIG_SOC_IMX35.

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>