firmware: imx: scu-irq: Remove unused export of imx_scu_enable_general_irq_channel

Since its introduction, this symbol has not been used by any loadable
modules. It remains only referenced within imx-scu.c, which is always built
together with imx-scu-irq.c

As such, exporting imx_scu_enable_general_irq_channel is unnecessary, so
remove the export.

Reviewed-by: Frank Li <[e-mail]>
Signed-off-by: Peng Fan <[e-mail]>
Signed-off-by: Shawn Guo <[e-mail]>

drivers/firmware/imx/imx-scu-irq.c

···
 
 	return ret;
 }
-EXPORT_SYMBOL(imx_scu_enable_general_irq_channel);