dsp_fbexport: use kzalloc

The dsp_export function calls omapfb_register_client() right after
allocating the memory with kmalloc.
A commit added to omapfb_register_client() a check on the value of
plane_idx in the notified block structure. As we're only using kmalloc,
you may end-up comparing garbage/random values (It even leads to a oops
on my n770).

Using kzalloc() fixes the issue.
Signed-off-by: Arnaud Patard <arnaud.patard@rtp-net.org>
Signed-off-by: Tony Lindgren <tony@atomide.com>

arch/arm/plat-omap/dsp/dsp_mem.c

@@ -1495,7 +1495,7 @@ static int dsp_fbexport(dsp_long_t *dspadr)
 #endif
 
 #ifdef CONFIG_FB_OMAP_LCDC_EXTERNAL
-	omapfb_nb = kmalloc(sizeof(struct omapfb_notifier_block), GFP_KERNEL);
+	omapfb_nb = kzalloc(sizeof(struct omapfb_notifier_block), GFP_KERNEL);
 	if (omapfb_nb == NULL) {
 		printk(KERN_ERR
 		       "omapdsp: failed to allocate memory for omapfb_nb!\n");