[MIPS] Alchemy: dbdma: add API to delete custom DDMA device ids.

Add API to delete custom DDMA device ids create with
au1xxx_ddma_device_add().

Signed-off-by: Manuel Lauss <[e-mail]>
Signed-off-by: Ralf Baechle <[e-mail]>

arch/mips/au1000/common/dbdma.c

···
 }
 EXPORT_SYMBOL(au1xxx_ddma_add_device);
 
+void au1xxx_ddma_del_device(u32 devid)
+{
+	dbdev_tab_t *p = find_dbdev_id(devid);
+
+	if (p != NULL) {
+		memset(p, 0, sizeof(dbdev_tab_t));
+		p->dev_id = ~0;
+	}
+}
+EXPORT_SYMBOL(au1xxx_ddma_del_device);
+
 /* Allocate a channel and return a non-zero descriptor if successful. */
 u32 au1xxx_dbdma_chan_alloc(u32 srcid, u32 destid,
        void (*callback)(int, void *), void *callparam)

include/asm-mips/mach-au1x00/au1xxx_dbdma.h

···
 u32 au1xxx_dbdma_put_dscr(u32 chanid, au1x_ddma_desc_t *dscr);
 
 u32 au1xxx_ddma_add_device(dbdev_tab_t *dev);
+extern void au1xxx_ddma_del_device(u32 devid);
 void *au1xxx_ddma_get_nextptr_virt(au1x_ddma_desc_t *dp);
 
 /*